Abstract
Natural product discovery from fungi for drug development and description of novel chemistry has been a tremendous success. This success is expected to accelerate even further, owing to the advent of sophisticated technical advances of technical advances that recently led to the discovery of an unparalleled biodiversity in the fungal kingdom. This review aims to give an overview on i) important secondary metabolite-derived drugs or drug leads, ii) discuss the analytical and strategic framework of how natural product discovery and drug lead identification transformed from earlier days to the present, iii) how knowledge of fungal biology and biodiversity facilitates the discovery of new compounds, and iv) point out endeavors in understanding fungal secondary metabolite chemistry in order to systematically explore fungal genomes by utilizing synthetic biology. An outlook is given, underlining the necessity for a collaborative and cooperative scenario to harness the full potential of the fungal secondary metabolome.
Key words: Analytics, antibiotics, bioprospecting, biosynthesis, chemotaxonomy
Introduction
This review is dedicated to Dr. David J. (“Dave”) Newman, formerly Chief of the Natural Products Branch (NPB) in the Developmental Therapeutics Program at the National Cancer Institute (NCI) in Frederick, Maryland. The current review was first thought to be a book chapter but since the book was not going to materialize after some time, we have decided to dedicate it to Dave as a paper. He has (fide Scopus, Nov. 2024) published over 190 papers, which received more than 36.000 citations and his h index is 58. His most well-known contributions are the reviews on the importance of natural products among the therapeutic agents that got published in the Journal of Natural Products (cf. Newman and Cragg 2020 for the latest update of this series). Dave is still active in the community even after his official retirement in 2015. We deeply respect his contribution to the field of natural product research and wish him all the best.
We will here outline the importance of fungi as sophisticated creators of secondary metabolites. In the course of their evolution, fungi have become highly creative and elaborate producers of such natural products, which display a high degree of structural diversity and novelty. This is commonly attributed to their immobile lifestyles and constant competition against other organisms (Spiteller 2008; Bills and Gloer 2016). Their unique and complex metabolites and biological effects have fascinated generations of natural product researchers of different fields in the past and present. For over a century, fungi served as a treasure trove for the exploration of natural products for the benefit of humankind. As early as 1893, mycophenolic acid (1), produced by the mold Penicilliumbrevicompactum, was discovered as the first antibiotic (Gosio 1893; Gosio 1896). Although 1 was not successfully commercialized as an antibacterial drug due to its toxic side effects, the semisynthetic derivative mycophenolate mofetil (2) has been launched to the market as a potent immunosuppressant about one hundred years later (Bentley 2000, Table 1). After WW II, the discovery of the penicillins (3) and their subsequent production in industrial scale opened the door to the “golden era of antibiotics” persisting for several decades (Hutchings et al. 2019). To date, thousands of secondary metabolites have been discovered with a wide range of biological properties. Some of them are usable for human benefit, while ingestion of others, such as mycotoxins that contaminate food, may have potentially fatal consequences (Ráduly et al. 2020). Between the late 1930’s and the late 1950’s, noteworthy anti-infective agents such as cephalosporin C (4) (Newton and Abraham 1955), pleuromutilin (5) (Kavanagh et al. 1951), fusidic acid (6) (Godtfredsen et al. 1962), and griseofulvin (9) (Oxford et al. 1939) were discovered from fungi. Further examples of early described compounds are the illudins (10–11) (Anchel et al. 1950), which have been studied extensively for their cytotoxicity. Over the next three decades, other important fungal metabolite classes were discovered, such as the cytochalasins (12–14) (Aldridge et al. 1967), myriocin (15) (Kluepfel et al. 1972 and Mapook et al. 2022), cyclosporin A (16) (Rüegger et al. 1976), the statins (17–19) (Endo 2008), the echinocandins (20–25) (Benz et al. 1974; Schwartz et al. 1989; Iwamoto et al. 1994; Hüttel 2021) as well as the strobilurins (26–27) (Anke et al. 1977; cf. Table 1).
Table 1.
Important natural products from fungi and common applications (reviewed by Bills and Gloer 2016; Hutchings et al. 2019; Newman and Cragg 2020).
class | discovery reported | producing organism | introduced into use | example | use |
---|---|---|---|---|---|
mycophenolic acids | 1893, myco-phenolic acid (1)a | Penicilliumbrevicompactum | 1995 | mycophenolat-mophetil (2, semi-synthetic derivative of mycophenolic acid) | immuno-suppressive (prevention of organ rejection following kidney, liver, heart transplant) |
kojic acid | 1907, kojic acidb | Aspergillus (flavus var.) oryzae | 1955 | kojic acid | antioxidant in cosmetic products used for skin lightening in Asian countries |
ergot alkaloids | 1918, ergotaminec | Clavicepspurpurea, C.fusidormis, C.paspali | 1921 | e.g. ergotamine tartrate, dihydroergotamine mesylate | vasoconstrictor (third-line therapy of migraine) |
1935, ergometrine (27)d | Clavicepspurpurea, C.fusidormis, C.paspali | 1936 | methylergometrin (semisynthetic derivative of ergometrine) | uterotonic (treatment of postpartum haemorrhage) | |
1967, ergocryptinee | Clavicepspurpurea, C.fusidormis, C.paspali | 1975 | bromocriptine (semi-synthetic derivative of ergocyptine) | treatment of reproductive disorders, Parkinson’s disease | |
β-lactams | 1929, penicillin G (3)f | Penicilliumrubens | 1943 | penicillins e.g. amoxicillin (29, semi-synthetic derivative of penicillin G) | antibiotic (against Gram-positive and Gram-negative bacteria) |
1945, cephalo-sporin C (4)g | Acremoniumchrysogenum | 1964 | cephalosporins e.g. cephalotin (33, semi-synthetic derivative of cephalosporin C) | antibiotic (against Gram-positive and Gram-negative bacteria) | |
phallotoxins | 1937, phalloidinh | Amanitaphalloides | - | phalloidin ae | F-actin staining, fluorescence microscopy |
gibberellins | 1938, gibberellic acidi | Fusariummoniliforme | late 1950’s | gibberellic acid | phytohormone for plant development used as biochemical in agriculture |
griseofulvin | 1939, griseofulvinj | Penicilliumgriseofulvum | 1959 | griseofulvin | antimycotic (therapy of skin, hair, and nails) |
illudins | 1950, illudins M (10) and S (11)k | Omphalotusilludens | under development | irofulvenaf (semi-synthetic analogue of illudin S) | anticancer (failed in clinical trials) |
pleuro-mutilins | 1951, pleuro-mutilin (5)l | Clitopiluspasseckerianus | 2019 | e.g. lefamulin (37, semisynthetic derivative of pleuromutilin) | antibiotic |
wortmannin | 1957, wortmanninm | Talaromyceswortmannii | - | wortmannin ag | anticancer, Pl3K-inhibitor in cell assays (failed in clinical trials) |
brefeldins | 1958, brefeldin An (decumbin) | Penicilliumdecumbens | - | brefeldin A ah | biochemical tool for the study of membrane trafficking and secretion |
psilocybin | 1959, psilocybin (38) o | Psilocybe spp. | under development | psilocybin (38) ai | major depressive disorder (not yet generally approved) |
fusidic acid | 1962, fusidic acid (6)p | Ramulariacoccinea | 1962 | fusidic acid (6) | antibiotic (against Gram-positive bacteria including methilicin-resistant Staphylococcusaureus) |
zearalenones | 1962, zearalenoneq | Fusariumgraminearum | 1969 | α-zearalenol (semi-synthetic derivative of zearaleone) | anabolic agent used as growth promoter in beef cattle and sheep in North America |
cytochalasins | 1967, cytochalasin A (12) and B (13)r | Pyrenophoradematioidea | development aborted | e.g. cytochalasin B (13)aj | antiviral, biochemical tool for the study of cell division and cell motility |
mizoribine | 1971, mizoribines (bredinin) | Penicilliumbrefeldianum | 1984 | mizoribine | immuno-suppressive in Japan, Korea, and China (used for renal transplants) |
myriocins | 1972, myriocin (15)t | Melanocarpusalbomyces, Isariasinclairii | 2010 | fingolimod (35, semi-synthetic derivative of myriocin) | immuno-suppressive (treatment of multiple sclerosis) |
cyclosporin | 1976, cyclosporin A (16)u | Tolypocladiuminflatum | 1983 | cyclosporin A (16) | immuno-suppressive (prevention of organ transplant and tissue graft rejection) |
statins | 1976, mevastatin (18, ML-236B) v | Penicilliumcitrinum | 1991 | pravastatin (19, semisynthetic derivative of mevastatin) | cholesterol lowering |
1978, lovastatin (17, mevinolin) w | Monascusruber; Aspergiluusterreus | 1987 | e.g. lovastatin (17), simvastatin (semisynthetic derivative of lovastatin) | cholesterol lowering | |
echino-candins | 1974, echinocandin B (20)x | Aspergillusdelacroxii | 2006 / 2023 | anidulafungin (semi-synthetic derivative of echinocandin B) / rezafungin (21, analog of anidulafungin) | antimycotic (first-line therapy against systemic infections) |
1989, pneumo-candin A0y (L-671,329) | Glarealozoyensis | 2001 | caspofungin (semi-synthetic derivative of pneumocandin B0) | antimycotic (first-line therapy against systemic infections) | |
1994, FR901379z (24, WF11899A) | Coleophomaempetri | 2005 | micafungin (semi-synthetic derivative of FR901379) | antimycotic (first-line therapy against systemic infections) | |
strobilurins | 1977, strobilurin A (26)ab | Strobilurustenacellus | 1996 | e.g. azoxystrobin (synthetic derivative) | agro-fungicide |
cyclodepsi-peptides | 1992, PF1022 Aac | Rosellinia spp. | 2005 | emodepsid (semi-synthetic derivative of PF1022 A) | anthelmintic, veterinary medicine |
enfuma-fungins | 2000, enfuma-fungin (40)ad | Hormonemacarpetanum | 2020 | ibrexafungerp (39, semisynthetic derivative of enfanufungin) | antimycotic (systemic infections) |
a (Gosio 1893; Gosio 1896); b (Saito 1907); c (Stoll 1918); d (Stoll 1935); e (Amici 1969); f (Fleming 1929); g (Newton and Abraham 1955); h (Lynen and Wieland 1938); i (Yubata and Sumiki 1938); j (Oxford et al. 1939); k (Anchel et al. 1950); l (Kavanagh et al. 1951); m (Brian et al. 1957); n (Singleton et al. 1958); o (Hofmann et al. 1958); p (Godtfredsen et al. 1962); q (Stob et al. 1962); r (Aldridge et al. 1967); s (Mizuno et al. 1974); t (Kluepfel et al. 1972); u (Rüegger et al. 1976); v (Endo et al. 1976); w (Alberts et al. 1980); x (Benz et al. 1974); y (Schwartz et al. 1989); z (Iwamoto et al. 1994); ab (Anke et al. 1977); ac (Sasaki et al. 1992); ad (Peláez et al. 2000); ae (Wulf et al. 1979); af (Gheysen et al. 2020); ag (Liu et al. 2005); ah (Chardin and McCormick 1999); ai (Kargbo 2020); aj (Cooper 1987).
These discoveries have provided valuable lead structures and pharmacophores for medicinal chemistry, contributing to the development of numerous drugs and market blockbusters (Fig. 1). According to the World Health Organization’s List of Essential Medicines in 2019, several fungal-derived metabolites are deemed essential for human healthcare. For instance, ergometrine (27), first isolated by Stoll in 1935, is utilized as an uterotonic following childbirth (Stoll 1935; McDonald et al. 2004). Additionally, griseofulvin (9) serves as an antimycotic agent for the treatment of dermatophytoses (Petersen et al. 2014) and the semisynthetic β-lactam antibiotics like ampicillin (28), amoxicillin (29), cefazolin (30), cefalexin (31), and ceftazidime (32), remain crucial antibacterial blockbusters, with a current annual market share exceeding 20 billion USD (Niego et al. 2023). After the discovery of cephalosporin C (4) (Newton and Abraham 1955) and its semisynthetic derivative cephalotin (33), which was marketed in 1964 as the first clinical cephalosporin antibiotic, a whole range of broad-spectrum semisynthetic cephalosporin antibiotics were approved (Lenore et al. 2000). Ceftaroline fosamil (34), the last (5th) generation cephalosporin with improved selectivity against multi-resistant Gram-positive bacteria, entered the market in 2011 (Critchley et al. 2011; Newman and Cragg 2020). An outstanding example of basic and applied research in pharmacy is the development of the semisynthetic echinocandins rezafungin (21), caspofungin (23), and micafungin (25), which are used as first-line treatment against invasive mycosis (Hüttel 2021). Here, optimized fermentation processes, modification of the product spectrum through mutagenesis, and improved activity and solubility due to chemical modification generated potent antifungal compounds (Hüttel 2021). Designed as a result of lead optimization efforts of joint research among Academia and the pharmaceutical industry around the structure of myriocin (15) (Kluepfel et al. 1972), initially discovered as an antifungal metabolite in 1972, fingolimod (35) was first synthesized in 1995 with reduced toxicity and improved immunosuppressive activity (Adachi et al. 1995; Volpi et al. 2019). After 15 years of preclinical and clinical studies, 35 has been approved in 2010 for the treatment of multiple sclerosis. By contrast, cyclosporin A (16), which is used to prevent rejection of organ transplants (Survase et al. 2011; World Health Organization 2019), is being used as an original natural product that is produced by fermentation of the ascomycete Tolypocladiuminflatum.
Figure 1.
Timeline of compounds developed into now Blockbuster drugs from Ascomycota (above) and Basidiomycota (below) together with their semisynthetic derivatives. The compounds are used as antibacterials (green line), antifungal compounds (blue line), and other indications (orange line).
Applied as the first top-sellers from Basidiomycota, the pleuromutilins (5, 36–37) are the latest class of antibiotics launched on the market for use in humans. Although pleuromutilin (5) was discovered in the early 1950’s (Kavanagh et al. 1951), its semisynthetic derivative retapamulin (36) entered the market in 2007 as a new class of antibiotics following a long innovation gap (Daum et al. 2007; Novak 2011). Noteworthily, the semisynthetic pleuromutilin antibiotic lefamulin (37) was recently approved by the EMA and is used for systemic treatment of bacterial infections in humans (Veve and Wagner 2018; Newman and Cragg 2020; Mapook et al. 2022). Other prominent fungal metabolites in use are the strobilurins (26–27) which are now established as one of the most important agents of agrochemical fungicides world-wide (Sauter et al. 1999). Based on mimetic synthesis, there are currently ten major derivatives on the market representing 23–25% of the global sales in the agrochemical sector (Anke 2020).
To date, fungal secondary metabolites continue to be exploited as a source for new drugs. An example for such a compound would be psilocybin (38, Kargbo et al. 2020), which is currently in clinical trials, while others were only recently approved. The latter applies to ibrexafungerp (39), a semisynthetic derivative of the triterpenoid enfumafungin (40) which was approved as orphan medicine (EMA 2021), as well as for the next-generation echinocandin rezafungin (21), a structural analog of anidulafungin (EMA 2024; see also Table 1).
Secondary metabolites are derived from central metabolic pathways, analogous to primary metabolites. The secondary metabolism in fungi is mostly encoded by genes organized in BGCs that encode dedicated enzymes to catalyze various reactions known from synthetic and organic chemistry (Keller 2019). Typical examples of natural product classes are i) the PKs, produced from malonyl- and Ac-CoA units formed by polyketide synthases; ii) NRP generated by using amino acids as templates; iii) the terpenoids, produced by terpene synthases and cyclases with isoprene units as basic building blocks, iv) alkaloids, generated from amino acids, and v) combinations thereof, such as meroterpenoids (mero = partial) (Fig. 2). Aside from these biosynthetic pathways, there are some rare ones discovered in fungi, such as the alkyl citrates, exemplified by the antimycotic sporothriolide (41) (Tian et al. 2020; Kuhnert et al. 2021). A rising number of secondary metabolites originating from ribosomally synthesized and posttranslationally modified peptides have been described over the last years (Bills and Gloer 2016; Walsh and Tang 2017; Keller 2019; Vogt and Künzler 2019). Examples for important secondary metabolites from fungi together with their semisynthetic analogues, categorized according to their biosynthetic origin, are given in Fig. 2.
Figure 2.
Examples of important natural products together with their semisynthetic analogues from fungi grouped by biosynthetic origin.
Over the last century, natural product discovery has undergone its own process of evolution. Although strategies for the isolation of natural products were less complex, chromatographic technologies relatively limited, and methods for structure elucidation at the very beginning, the early stage of natural product research (1940s–1970s) was very productive (Katz and Baltz 2016; Karwehl and Stadler 2017). Nowadays, significant improvements in analytical techniques, assessment of the potential prolificity of a surveyed strain by genome mining, biological manipulation together with engineering strategies, and microbial culturing have made this laborsome work far more efficient (Atanasov et al. 2021). Hence, it can be expected that continuous technical advancements will further catalyze the description of many more thousands of secondary metabolites, waiting to be characterized also for potential biotechnological applications (for an overview of some remarkable secondary metabolites used in biotechnology, cf. Hyde et al. 2024). In the following, we will give examples of different approaches to evaluate and describe the secondary metabolome of fungi.
Fungal-derived natural product discovery – methodologies from the past to the future
Reflections of the past – Seeing is believing
Many secondary metabolites were discovered from fungi sparked by the fascination for promising bioactivities, harmful poisons, or colorful pigments. In particular, fungi exhibit a variety of colors and color changes, which attracted the attention of organic chemists, facilitated by the fact that pigments were visible during the separation process. Bright pigments such as the pulvinic acids (42–45) and the grevillins (46–47) were already isolated in the 1960s and 1970s from the basidiomata of the Boletales (Fig. 3; Gill and Steglich 1987). Due to the advent of sophisticated chromatographic and spectral techniques, many additional, complex and fascinating pigments have since then been discovered. Those include the orange-brown naphtaloid pulvinic acids badione A (48) and norbadione A (49) from the cap skin of the Bay Bolete (now called Imleriabadia or Xerocomusbadius) (Steffan and Steglich 1984), the bright yellow triquinanoid pulvinic acid sclerocitrin (50) (Winner et al. 2004) from fruiting bodies of Sclerodermacitrinum, and the blue colored sanguinones (51–52) from Mycenasanguinolenta (Peters and Spiteller 2007). Besides the intriguing colors of fruiting bodies of Basidiomycota, the stromata of Ascomycota have been shown to be a prolific source of pigments as well (Caro et al. 2015). During a study on stromatal extracts of Hypoxylonfragiforme, 19 complex pigments of the fragirubrin- (53), mitorubrin- (54), rutilin- (55), and hydrorubrin-types (56) were isolated, demonstrating the great diversity of azaphilones in H.fragiforme (Becker et al. 2021). Notably, archeological dating methods and analytical chemistry suggested the prevalence of these pigments over millennia in fossilized stroma (Surup et al. 2018a).
Figure 3.
Examples for the structural diversity of pigments from fungi.
Recent advances – Technical innovations driving modern natural product discovery
At the outset of natural product discovery, NMR spectroscopy was still in its infancy and large amounts of metabolites were needed for basic experiments. For instance, in 1963, a proton NMR spectrum at 60 MHz was performed with amounts of 20–30 mg of the compounds, as Shibata demonstrated for the structure of ustilaginoidin A (57) (1963). Structures of unknown metabolites were mostly solved by means of organic synthesis strategies like degradation or derivatization reactions (Beaumont et al. 1968; Steglich et al. 1970), or in tandem with synthesis and NMR spectroscopy. Commonly applied chromatography techniques for the isolation of fungal metabolites comprised column chromatography on NP (e.g. silica gel), or SEC (e.g. SephadexTMLH-20) as well as TLC. Another strategy follows crystallization procedures, as used, for example, for the isolation of pulvinic acid derivatives (44–45) or anthraquinone derivatives (Madhosingh 1966; Beaumont et al. 1968; Edwards 1977; Besl et al. 1978). Over time, experimental basics for the discovery of new compounds – such as screening, extraction and isolation of pure compounds – remained largely unchanged. Significant advancements, like the integration of hyphenated instruments, the application of AI, the diversification of chromatographic solutions and the increase in sensitivity, have complemented these basics substantially (Table 2; Newman and Cragg 2020). Isolation and structure elucidation of new compounds can now be achieved more rapidly and with decreasing sample amounts, so that even minor constituents of extracts are attracting growing attention in the discovery of fungal metabolites.
Table 2.
Technical advances and new strategies in natural product chemistry.
field | development | impact | example | |
---|---|---|---|---|
NMR spectroscopy a | instrument properties | high-field NMR (e.g. 600 MHz, 800 MHz, 900 MHz) | increased sensitivity and quality | nematoctone (58) from Hohenbueheliagrisea (0.6 mg sample amount, 5 mm cryoprobe, shigemi tube, 700 MHz)b |
microprobes (reduced diameter [1–3 mm; 10–140 µL], shigemi tubes, microcoil flow) | increased sensitivity towards enhanced signal to noise ratio (S/N) | |||
cryogenic probes | ||||
sophistica-ted 2DNMR experiments | homo- [1H-1H and 13C-13C], heteronuclear [1H-13C, 1H-15N, 13C-15N] direct and (ultra-)long-range experiments (LR-HSQMBC, LR-serHSQMC) | for challenging structures (e.g. low sample amount, highly proton-deficient core structures, weak heteronuclear correlations) | structure revision of coniothyrione (59, moderate antibacterial) from Coniothyriumcerealis (1.2 mg sample amount, 1.7 mm MicroCryo-ProbeTM, 600 MHz)c | |
computa-tional tools | computational modeling of 1H, 13C chemical shifts (hierarchical organization of spherical environments [HOSE] code algorithms in combination with machine learning methods [ML]) | assistance in structure elucidation and verification | (±)-versiorcinols A (60a, 60b, moderate antibacterial) from Aspergillusversicolor (gauge independent atomic orbital [GIAO], spin-spin coupling constants [SSCCs])dmicroketide A (61, antifungal) from Microsphaeropsis sp. (GIAO)e | |
computer assisted structure elucidation (CASE) software creating a molecular connectivity diagram (MCD) | ||||
mass spectrometry f | instrument properties | ionization source (electrospray ionization [ESI], matrix-assisted laser desorption/ionization [MALDI], desorption electrospray ionization [DESI]) | increased application range | in situ study on fungal metabolites in (co)-cultures (DESI-MS imaging) g |
(high-resolution) mass analyzer (time-of flight mass spectrometry [TOFMS], quadrupole mass spectrometry [QMS], QTOF, ion trap, Orbitrap) | increased sensitivity, speed and quality; for MS/MS applications | quantification of trace levels of triterpenoids in Ganodermalucidum (UPLC-ESI-HR-QTOF-MRM)h | ||
combined techno-logies | separation techniques (ultra high performance liquid chromatography [UHPLC], ion mobility spectrometry [IMS]) | increased resolution and speed of analysis; for HTS applications | screening of ≈13.000 fungal extracts (HTS profiling via UHPLC-MS)l | |
hyphenated techniques i | Instru-mentation | coupling high performance liquid chromatography (HPLC), NMR, IMS, circular-dicroism (CD), or SPE (e.g. LC-NMR, LC-IMS, LC-CD, LC-SPE-NMR) | on-line analysis of complex biological matrices (e.g. unstable metabolites) | malbranpyrrole A (62, cytotoxic) from Malbrancheasulfurea (LC-SPE-NMR, photosensitive polyketide)j |
chromato-graphy k | combined techno-logies | 2D-LC techniques | increased peak capacity, selectivity and resolution; for preventing degradation of unstable compounds | cytoglobosin Ab (63) from Chaetomiumglobosum (preparative MPLC × HPLC system)m |
material | reversed phase (RP), hydrophilic interaction chromatography (HILIC), core-shell particles, chiral stationary phases | increased resolution | (±)-penicilliodes C (64a, 64b) from Penicillium sp. (separation on chiral stationary phase)n | |
comple-mentary approaches o | computa-tional tools | dereplication | wide analyte coverage, increased sensitivity and selectivity; for HTS applications | oligoisoprenoids and styrylpyrones from Gymnopilusimperialis (dereplication via GNPS)p novel azaphilones from Parahypoxylon spp. (UHPLC-DAD-IM-MS/MS)q |
untargeted (MS)-based metabolomics |
a (Fukushi 2006; White et al. 2008; Senior et al. 2013; Halabalaki et al. 2014; Sergey et al. 2014; Williamson et al. 2014; Elyashberg 2015; Martin et al. 2015; Andernach et al. 2016; Wolfender et al. 2019; Motiram-Corral et al. 2020; Elyashberg and Argyropoulus 2021); b (Sandargo et al. 2018); c (Ondeyka et al. 2007; Martin et al. 2013); d (Gu et al. 2017); e (Liu et al. 2020a); f (Arevalo et al. 2019; Dodds and Baker 2019; Masike et al. 2021); g (Sica et al. 2014); h (Kaewnarin et al. 2021); i (Gebretsadik et al. 2021); j (Yang et al. 2009); k (Gritti et al. 2007; DeStefano et al. 2008; Chen et al. 2012; Stoll and Carr 2017; Atri et al. 2019; Zeng et al. 2019; Brandão et al. 2020); l (Ito et al. 2011); m (Yan et al. 2016); n (Wei et al. 2019); o (Bitzer et al. 2007; Li et al. 2022; Palermo 2023); p (Caldas et al. 2022); q (Cedeño-Sanchez et al. 2023).
Figure 4.
Examples for challenging structures in the discovery of natural products of fungi.
Workflow – from the fungus to the compound
Sources of novel metabolites and the importance of taxonomy
To study the natural product chemistry of fungi, the biological material for examination must naturally be obtained first. For this purpose, fungal material collected from various geographic or ecological contexts – in accordance to local and global regulatory law –, can be used (step I, Fig. 5). Readily visible fruiting structures (e.g. ascomata and basidiomata of macrofungi) can be collected during field trips and pure cultures isolated from their spores or their mycelial tissue (step II, Fig. 5). Subsequently, they can be cultivated (step III, Fig. 5). Based on micro- or macro-morphological characters and DNA sequence data, a sound determination of a fungus’s taxonomic affinities is essential to ensure the identity of the collected (and isolated) organisms, together with the deposition of vouchers in official biodiversity repositories. The pitfalls of inadequate or inaccurate taxonomic treatments of important secondary metabolite producers can be seen in two independent examples: a) The producer of the cyclodepsipeptide PF1022A, which is semi-synthetically modified to yield the marketed nematicidal drug emodepside, was only tentatively assigned to Rosellinia and allies in a patent application by Harder et al. (2011). Only later, Wittstein et al. (2020) unambiguously demonstrated that ascospore-derived isolates of members of the genere Rosellinia and Astrocystis were indeed able to produce derivatives of the PF1022 family and concurrently resurrected the genus Dematophora in the course of a taxonomic study for plant pathogenic Rosellinia, that curiously were not able to produce PF1022 derivatives.
Figure 5.
Different strategies for the exploitation of fungal sources (Photos: Lillibeth Chaverra-Muñoz (III); Hedda Schrey (II, IV, VI, VIII); Nina Sandmann (V, VII); Frank Surup (IX).
Another striking example for the concise identification of important fungal strains that were historically reported to produce bioactive compounds treats the alleged producer of taxol, formerly classified as Taxomycesandreanae. The genus Taxomyces was originally erected by Strobel et al. (1993) for an endophyte isolated from the taxol-producing Yew tree Taxusbrevifolia. The authors postulated that endophytic fungi could produce the plant metabolite and discussed the possibility of horizontal gene transfer between the endophyte and its host. Notably, there is absolutely no evidence for such a phenomenon until today, and it is not plausible because the taxol biosynthesis genes are not even clustered. Many studies followed that claimed the detection of taxol in other endophytic ascomycetes from Yew and even many other plants that do not even produce taxol. None of those studies provided unambigious proof demonstrating that this highly complex molecule can indeed be produced by a fungus. The methodology used was inadequate as no preparative isolation and characterization of natural products by NMR spectroscopy and other salient methods described below was conducted. Later, Heinig et al. (2013) reported that they were unable to find the taxadiene synthase gene, which is essential for taxol biosynthesis, in an Illumina-based genome of the fungal ex-type strain (Heinig et al. 2013). Unfortunately this valuable contribution was largely ignored by principal investigators who drove their students into a dead end, the publication of inconclusive studies – and in particular, reviews that cited those and other inconclusive reviews, did not stop. Based on genome mining for the phylogenetic marker genes, as well as on microscopic studies of the holotype specimen, Cheng et al. (2022) now found out that Taxomyces is not even an ascomycete, but a basidiomycete which was assigned to the genus Ceriporiopsis (Cheng et al. 2022). This finding made the possibility of horizontal gene transfer even more improbable. Stadler and Kolarik (2024) as well as Gärditz and Cessnick (2024) have critically discussed this phenomenon in the context of scientific integrity and tried to provide a rationale that will hopefully prevent the scientific papermills from spreading nonsense and also direct the supervisors of young scientists to more attractive research goals. While endopytic fungi and many other environmental isolates that represent sterile mycelia could hardly be identified to the genus or species level in the 1990s, this has now changed with the advent of molecular phylogeny and genomics. Even non-specialists such as natural product chemists are increasingly resorting to molecular data for characterization of their producer strains, however, they often only use ITS nrDNA, which does not necessarily yield conclusive results on the identity of their strains. It is hence strongly recommended for non-specialists working with fungi as sources for biologically active compounds to carefully read the recommendations by Raja et al. (2017) and to act accordingly. Ideally, interdisciplinary collaborations with mycological taxonomists would be of profound interest for both fields, natural product research and taxonomy alike.
Since the production of secondary metabolites often differs between fruiting bodies harvested in nature and cultured vegetative mycelia in the lab, various strategies have been established to aquire novel compounds from fungal sources. Fruiting bodies, on the one hand, are often only available in limited quantities owing to their short appearance during the mushroom season. Moreover, a holistic chemical characterization of small-sized fruiting bodies can be very challenging, especially if they belong to rare taxa, due to the fact that often more than 50 g (fresh weight) are needed, as exemplified for the isolation of the red diketopiperazine alkaloids rosellins A and B (64–65; Fig. 6) from Mycenarosella, a tiny mushroom with a cap diameter of only 1–2 cm (Fig. 13, Lohmann et al. 2018). Therefore, an important point to consider is the storage of organic material for subsequent isolation of secondary metabolites, as well as their treatment (e.g. fresh, dried or frozen; Himstedt et al. 2020; step IV, Fig. 5). In contrast, fresh fruiting bodies have often been used for injuring experiments. As a consequence to physical injury of the fungal tissue, wound-activated chemical responses can elicit different secondary metabolites compared to intact fruiting bodies in the framework of a chemico-ecological adaptation strategy (Himstedt et al. 2020). Other fields of use for fresh fungal material are feeding experiments of living fruiting bodies in their natural environment with 13C- or 14N-labeled precursor molecules for the investigation of biosynthetic pathways. A successful example for monitoring hypothetical pathways is the incorporation of [1,2-13C2]-acetate during the biosynthesis of aminotenuazonic acid (66) in fruiting bodies of Laccariabicolor, a 3-acyltetramic acid derivative which might be derived from (2S,3S)-3-methylornithine and acetoacetyl-CoA (Schrey et al. 2019a).
Figure 6.
Chemical structures of the rosellins A and B (64–65), aminotenuazonic acid (66), and the laxitextines A and B (67–68).
Figure 13.
Morphological diversity of Ascomycota. Cookeinatricholoma (A), Blackwellomyces sp. on Lepidopterapupa (B), Metarhizium sp. on adult cicada (C), Daldiniaeschscholtzii (D), Hypoxylonhaematostroma (E), Beauverialeioensis (F), Fusarium sp. (G), Squamotuberaleratii (H), Xylaria sp. (I), Xylariacubensis (J), Xylaria spp. (K, L), Penicilliumexpansum in culture (M), Aspergilluschevalieri in culture (N), anamorph structures of Aspergilluschevalieri (O), anamorph structures of Fusariumredolens (P), anamorph structures of Penicilliumexpansum (Q). Photos: courtesy of NBT Plant Microbe Bank, National Biobank of Thailand, National Center for Genetic Engineering and Biotechnology, Thailand (A, D, E, H–L); courtesy of Plant Microbe Interaction Research Team, National Center for Genetic Engineering and Biotechnology, Thailand (B, C, F); Cobus Visagie (G, M–Q).
Mycelial cultures, on the other hand, can easily be expanded for experiments after successful isolation of the pure strains on culture plates. Transferring the organisms to submerged or solid cultures are standard procedures to induce the production of secondary metabolites (step III, Fig. 5). Different media compositions and fermentation conditions can be evaluated in small-scale screening experiments accompanied by analytical methods to evaluate chemical diversity in crude extracts and to designate worthwhile targets for chemical isolation and characterization (step V, Fig. 5). Dereplication – the systematic comparison of spectroscopic data for distinct components of a complex extract with the literature or databases to avoid the isolation of undesired or known secondary metabolites – constitutes an early-stage pre-selection method and can act as a major timesaver (Bitzer et al. 2007; Nielsen et al. 2011; Stadler et al. 2014; Gaudêncio and Pereira 2015; Nielsen and Larson 2015; Wolfender et al. 2019). Dereplication is often done by UHPLC, especially in high-throughput screening scenarios, coupled by DAD and HRMS and HRMS/(MS)n in combination with chemical structure database searches, for example using CAS SciFinder (ca. 183 million compounds), PubChem (ca. 110 million compounds), ChEMBL (ca. 2.1 million compounds), or Dictionary of Natural Products (ca. 328.000 natural compounds). Bioactivity-guided fractionation using a phenotypic screening approach is typically used to evaluate crude extracts, as exemplified by the discovery of the laxitextines (67–68) from cultures of the basidiomycete Laxitextumincrustatum (Mudalungu et al. 2015).
Increasing the amount of (crude) extract material by repeating a fermentation in multiple batches or increasing culture volume may be necessary to allow the subsequent isolation of sufficient amounts of pure compound for structure elucidation and broad biological characterization. After separation of biomass and supernatant (only necessary in case of submerged cultures), a variety of extraction techniques and chromatographic strategies (step VI, Fig. 5), elaborately discussed in several reviews (Pucci et al. 2009; Latif and Sarker 2012; Bucar et al. 2013; Marlot and Faure 2017; Sahu et al. 2018; Zuvela et al. 2019; Brandão et al. 2020; Kim and Marriott 2021), are available and summarized in Fig. 7.
Figure 7.
Techniques and chromatographic strategies for isolation of natural products from fungi. Prepared using biorender.com.
Structure elucidation of novel metabolites and screening libraries
After isolation of the pure compounds, their chemical structure can be determined by 1D and 2DNMR spectroscopy and HR-MS experiments (step VII, Fig. 5). Practical strategies for the structure elucidation of small molecules have thoroughly been reviewed (e.g. Kwan and Huang 2008; Breton and Reynolds 2013; Reynolds and Mezzola 2015) and even published in detail in book articles (e.g. Mangoni 2012; Linington et al. 2015). The stereochemical determination of chiral molecules is still a major concern in drug discovery because stereoisomers can considerably differ in potency, toxicity, and behavior (pharmacodynamics). Assigning the absolute configuration can be one of the most challenging tasks in structure elucidation even though a variety of methods have been established. Certainly, total synthesis followed by comparison of the analytical and chiroptical data of the natural and synthetic product (Schrey et al. 2019a), or X-ray crystallography (Mechlinski et al. 1970) are the gold standard to determine the absolute configuration. Notably, numerous examples for structure revisions via total syntheses have been reported, as demonstrated for strobilurin A (26) (Anke et al. 1984), the azaphilone chaetoviridin A (69) from Chaetomium spp. (Makrerougras et al. 2017; Fig. 8), the protoilludane type sesquiterpenoid repraesentin F (70) from basidiomes of Lactariusrepraesentaneus (Ferrer and Echavarren 2018), or a harziane diterpenoid from Trichodermaatroviride (Hönig and Carreira 2020). However, in many cases, natural products are very difficult or even impossible to synthesize in a cost efficient manner and in larger quantities due to their complex structures and the number of chiral centers. Hence, not all of these compounds are applicable for synthesis or suitable for crystallization. As discussed before, during the last decades, technological progress has improved NMR spectroscopy to enable its use as a powerful tool for the stereochemical determination of chiral molecules. Dipolar coupling analysis (NOESY and ROESY) in conjunction with 1H-1H scalar couplings are the preferred methods for the stereochemical elucidation of cyclic molecules, recently used for the conformation of the eight-membered heterocycles E/Z-proxamidines (71–72) (Schrey and Spiteller 2019). In contrast, acyclic and macrocyclic molecules contain carbon chains with higher flexibility allowing multiple slowly interconverting rotamers to be present in the NMR spectrum. To solve these problems of assigning the relative configuration, J-based configurational analysis (JBCA, known as ‘Murata’s method’) has been implemented in structure elucidation with great success (Matsumori et al. 1999). This method considers 3JH-H and 2,3JH,C coupling constants to assign anti or gauche relationships of vicinally substituted chains, successfully applied for determination of the relative configuration of e.g. rickiol A (73) (Surup et al. 2018b) and simplicilone A (74) (Anoumedem et al. 2020). The 1H-1H and 1H-13C coupling constants are typically measured indirectly through a combination of NMR experiments (Surup et al. 2018b; Anoumedem et al. 2020). Aside from residual dipolar coupling analysis, which was used to assign the relative configuration of curtachalasin D (75) from Xylariacf.curta (Wang et al. 2019c), the concept of a universal NMR database approach from Kishi’s group is worth mentioning for stereochemical assignment of polyketides (Kobayashi et al. 1999; Lee et al. 1999; Kobayashi et al. 2000a; Kobayashi et al. 2000b; Kobayashi et al. 2001). Based on systematic observations of differences in 1H NMR and 13C NMR chemical shifts of synthesized highly functionalized and acyclic model compounds, numerous NMR data-sets of stereoclusters are available for comparison and determination of natural products with unknown stereochemistry containing the respective structural motif (Matsumori and Murata 2017; Ma et al. 2020).
Figure 8.
Examples for molecules where it proved challenging to establish the absolute configuration.
For establishing the absolute configuration, derivatisation reactions as well as shift reagents (Jiménez-Romeo et al. 2010) have often been used. Known as Mosher’s method, i.e. derivatization with MTPA followed by analysis of NMR chemical shift differences of the MTPA esters, represents the most widely used tool for the assignment of secondary hydroxyl functions (Dale et al. 1969). Problems can arise when the molecule features multiple functional groups, such as alcohol or amino groups, leading to several reaction products. For the stereochemical assignment of amino acid constituent units, hydrolytic cleavage and derivatization of the resulting amino acid with a chiral reagent followed by subsequent comparison of the diastereomer with authentic (synthetic) samples of known configuration on achiral column materials via HPLC or GC deliver the absolute configuration of chiral compounds. This strategy has been established as Marfey’s method and other methods derived thereof (Marfey 1984; Vijayasarathy et al. 2016; Schrey et al. 2019b; Harms et al. 2021). Aside from NMR chiral solvating agents (Pedras et al. 2005), the crystalline sponge method can be implemented in absolute configurational analysis of complex novel metabolites, as demonstrated for the determination of the absolute configuration of the sesterterpene astellifadiene (76) from “Emericella” (correctly referable to Aspergillus in current One-Fungus-One-Name-based taxonomy!) variecolor, which was heterologously expressed in Aspergillus (flavus var.) oryzae (Matsuda et al. 2016). Each method has its specific limitations and it is often necessary to combine two or more methods. For instance, the stereochemical analysis of rickiol A (73), JBCA in conjunction with Kishi’s method was applied to establish the relative configuration, followed by Mosher’s method for the absolute configuration (Surup et al. 2018b). On a last note, we wish to comment on the usage of ECD, which is based on the comparison of experimental ECD and calculated ECD spectra, as it has become a sought-after tool for establishing the absolute stereochemistry of natural products (Li et al. 2010; Superchi et al. 2018). ECD calculations, which to our experience are often requested during the review process, should be used more carefully, as the corresponding calculations are often very time-consuming and may occupy a supercomputer for several months for one stereoisomer, especially for complex natural products with many stereocenters. This specifically applies for molecules that are already defined by X-ray crystal structures or their biosynthesis, to prevent the waste of unnecessary resources. Calculation-based methods have even led to incorrect assumptions in the past (Schmiedel et al. 2018).
Irrespective of isolation strategy or compound priorization, it is opportune to collect isolated substances and extracts in screening libraries both to access their biotechnological potential and to help with dereplication at the beginning of isolation campaigns (Stadler and Hellwig 2004; Bitzer et al. 2007; Barnes et al. 2016). While the search for novel carbon skeletons is rewarding, as the chance of finding novel bioactivities or targets is higher, isolating and screening highly similar compounds (and knowing by which taxonomic groups they are produced) can help with establishing a structure-activity relationship, which is useful information for later lead optimization by medicinal chemists (Stadler and Hellwig 2004; Bauer and Brönstrup 2014; Guo 2017; Silva and Emery 2018; Atanasov et al. 2021).
Bioreactor process development for promising candidates
Sufficient quantities for lead structure development and clinical trials are needed when evaluating the suitability of a compound to serve as a drug lead. To increase product yields as well as production titers, fermentation volume can simply be increased (e.g. 15 L, 350 L bioreactors; step IX, Fig. 5). In order to ensure stable production titers and yield, the fermentation process needs to be developed priorly, involving optimization of culture media, process conditions, and process parameters, together with complex analytical and preparative chromatography. A thriving example for a successful upscale within the Basidiomycota was the optimization of the production process of illudin M (10) produced by Omphalotusnidiformis. Development of a scalable and low-cost downstream process together with a robust transfer of gram quantities from shake flask to stirred tank paved the way for its potential application as precursor for semisynthetic anticancer agents (Chaverra-Muñoz et al. 2022; Chaverra-Muñoz and Hüttel 2022).
In contrast to in-culture produced compounds, a substantial amount of promising compounds are exclusively isolated from fruiting bodies. Scale up of those compounds would require extensive amplification of the biomass of a given producer organism and tends to be especially difficult or even impossible, given that the vast majority of fruiting bodies cannot be grown, or induced, artificially due to a variety of reasons. One, apart from the many biological reasons, is simply related to the Cost of Goods as production for industrial applications would often not be feasible. Other economic problems are associated with culture media difficult to scale, such as solid-phase media, and low production titres for which yield optimization using the aforementioned methods failed so-far, preventing their industrial applicability. In these cases, bioengineering tools are available, for which the antibiotic pleuromutilin (5), a tricyclic diterpene, is a successful example. Here, the recently discovered biosynthetic gene cluster comprising seven genes was heterologously expressed in Aspergillusoryzae. The successful reconstruction in A. (flavus var.) oryzae increased the production of pleuromutilin (5) significantly to more than 20-fold compared to the wild-type producing organism, Clitopiluspasseckerianus, which turned out to be crucial for its development as a commercial drug (Bailey et al. 2016).
On another note, fermentation, or even total biosynthesis might constitute powerful methods for the production of desired drug candidates, especially when considering to sustainably make use of waste streams in the frame work of a circular economy and in general, environmentally friendly conditions (Cox 2024). However, these ideas have to be brought to fruition first and until then, traditional strategies, like for example chemical total synthesis or synthesis inspired by biosynthesis in the frame of biomimetic reactions can do the job, as is the case, for example, for the production of the strobilurins or the statins (17, 19).
Biological aspects
Classical fermentation experiments – One strain, many compounds
Before the vast hidden chemical diversity of microorganisms and fungi became apparent using modern molecular biological and bioinformatic tools, the effect of even small changes in the composition of culture media and cultivation conditions was already noted and documented by empirical evidence. This includes the influence of culture aeration during fermentation (aspinolides, aspinonenes and aspyrones; Fuchser and Zeeck 1996) as well as the addition of supplements such as sodium bromide (hexacyclinic acid, Höfs et al. 2000). Observations for the variability of the secondary metabolite production under standardized laboratory conditions have been unified under the OSMAC hypothesis (see Bode et al. 2002). The hypothesis follows the idea that changes in environmental factors serve as impulses to the metabolic and ultimately the biosynthetic program of the surveyed organism to adapt to its current surrounding, as is programmed by the genetic code. For bioprocess development, several scenarios can be tested in dependency of the technical and experimental setup: impact of pH control, shear stress, process temperature, and oxygen supply (controlled by biotechnological machinery). Media components, especially considering its source (C/N ratio), can be crucial, but can also deliver important precursors (Rinkel and Dickschat 2015), effectors (glucose catabolite repression in A.flavus; Fasoyin et al. 2018), and inductors (glycerol in cephalosporin production; Shin et al. 2010). Even the culture morphology, which can be controlled by altering the growing environment with inert minerals (Antecka et al. 2016; Veiter et al. 2018) or the transfer of the process to solid growth media instead of liquid cultivation (Son et al. 2018), as well as light stress, can have meaningful influence on the production of secondary metabolites. Many fungi are able to sense light with the help of photosensitive proteins (Fuller et al. 2014; Lawrinowitz et al. 2022), which can contribute to the pigmentation of a fungal culture, an important causal factor shown to accompany growth stage progression (Yu and Fischer 2019). While these traditional variations in growth conditions lead to the discovery of several thousands of natural products and is usually among the first strategies to chemically characterize new species of interest, the number of found secondary metabolites is usually far lower than the number of predictable biosynthetic gene clusters, which remain ‘silent’ in standardized fermentation experiments. Strategies to activate these silence clusters include the co-cultivation with potential competitors or potential biosynthetical precursors (Fischer et al. 2016; Zhang and Elliot 2019). However, such strategies have limited use for industrial applications, as scale-up of such processes is not easy. For example, scale-up of a dual culture system is often already problematic when attempting to transfer production from agar plates to shake flasks.
Regulation and appearance of secondary metabolites encoding gene clusters in fungi
Secondary metabolites are products of an orchestrated genetic machinery, which mostly, but not necessarily, occur clustered in a pathway dependent manner (Rokas et al. 2018). Physical transcriptional access to these clusters is regulated by chromatin packaging (euchromatin, active; hetereochromatin, inactive), which itself is governed by a number of post-transcriptional (epigenetic) modifications of the associated histones forming the nucleosome (Gacek and Strauss 2012). Transcriptional regulation of BGCs can either be conceived to act in a local, cluster-specific way or globally, by e.g. affecting chromatin packaging (such as the previously discussed abiotic factors). Some of the best studied examples stem from the work on Aspergillus, Penicillium and Fusarium, probably due to their implications on human health as pathogens (e. g. A.fumigatus); being important plant pathogens (e.g. Fusarium spp.); or due to their biotechnological importance (e.g. P.chrysogenum). An example for global transcriptional regulators are members of the velvet-complex (VelB/VelA/LaeA) in A.fumigatus and A.nidulans, which have been described to govern fungal development, including its secondary metabolism (Perrin et al. 2007; Bayram et al. 2008). Another global regulator of fungal behavior was found in transcriptional studies of F.graminearum with FgStuA, a transcriptional factor exhibiting a highly conserved APSES amino acid sequence domain (see Zhao et al. 2015). Targeted deletion diminished transcription of well-known secondary metabolite encoding genes of the trichothecene and aurofusarin families and concurrently lead to loss of spore production, indicating a link of developmental stage and secondary metabolism (Lysøe et al. 2011). A transcription factor involved in oxidative stress response of A.parasiticus, AtfB was shown to bind to sequence motifs involved in aflatoxin biosynthesis (Roze et al. 2011). In Trichodermareesei, the deletion of the repressor of xylan degradation Xpp1 led to an increase of detectable transcripts predicted to be involved in polyketide biosynthesis (Derntl et al. 2017). In Beauveriabassiana, the transcription factor PacC, previously shown to steer responses to changes in the surrounding pH value (Tilburn et al. 1995), is involved in the regulation of bassianolone B production (Luo et al. 2017). In these examples, genetic targeting enabled the investigation of how environmental cues govern the expression of genes via transcription factors at the top of the hierarchy, ultimately steering which genes are activatable at a given moment and which not. The mode of transcriptional regulation for the vast majority of BGCs is, however, unknown and the clusters products hence inaccessible in standard laboratory conditions. Whether this is entirely due to the lack of specific signals leading to unfavorable chromatin packaging, their deactivation in the absence (or presence) of specific signals effected by biotic or abiotic factors, or even due to them being non-functional, is equally unclear (Gacek and Strauss 2012; Rokas et al. 2018; Collemare and Seidl 2019; Rokas et al. 2020). Collemare and Seidl (2019) argued that the field focused only on a handful of well-studied post translational modifications, such as histone acetylation and deacetylation (which can also be manipulated by using chemical inhibitors) affecting chromatin packaging and that more complex, multi-level regulatory mechanisms may be at play. It will be interesting to explore these potentially complex regulatory modes, which might open more directed ways of designing empirical studies to evaluate a strains productive capacities. Key to this will be broad genomical and genetical accessibility of fungal strains. Until then, other approaches are necessary to activate and elucidate the products of cryptic, untranscribed gene clusters, such as expression of the target cluster in a heterologous host, which will be further discussed in section 1.5. For additional information on the evolutionary origin of biosynthetic gene cluster formation and its regulation, we want to direct the inclined reader to other recent reviews covering the available published scientific literature (Collemare and Seidl 2019; Rokas et al. 2020).
Ecological context of secondary metabolites produced by fungi
Fungi co-exist with scores of other organisms in their natural habitats. They need to deal with competitors, predators, and UV radiation for sufficient nutrition, space, and survival (Keller 2019). For millions of years during the process of evolution, fungi have developed strategies to secure their survival in highly competitive ecological niches.
Because of their immobility, they have developed a multitude of chemical defense strategies to defend themselves against fungi, bacteria, springtails, nematodes, insects, and other fungivores. The ecological roles of secondary metabolites from fungi have been elaborately reviewed (Rohlfs and Churchill 2011; Spiteller 2015; Macheleidt 2016; Keller 2019). In analogy to plant-herbivore interactions, fungi employ various strategies: constitutive chemical defense, wound-activated defense, and induced chemical defense (Spiteller 2008). Chemical defense agents can be toxic constituents, or bitter and pungent compounds with highly functionalised carbon skeletons equipped with chirality and biological activity (Fig. 9). To determine an ecological function of a secondary metabolite or to understand and investigate its mode of action can be a daunting task. In some cases it is possible to deduce the function from a strong biological activity, for instance ibotenic acid (77), an active constituent of the fly agaric (Amanitamuscaria) with its insecticidal activity or the antifungal 4-methoxy strobilurin A (84), isolated from Mucidulamucida (syn. Oudemansiellamucida) (Vondráček et al. 1983). Other examples constitute muscimol (78), and muscazone (79), which act as gamma-aminobutyric acid receptor affecting the central nervous system (Lee et al. 2018; Rivera-Illanes and Recabarren-Garjardo 2024). Additional important toxic components are α-amanitin (80) and phalloidin (81) from A.phalloides or the nephrotoxine orellanine (82), present in the fruiting bodies of Cortinariusorellanus and C.rubellus causing serious mushroom poisoning, as well as the psychotropic psilocin (83) from many Psilocybe species. However, there are others where extrapolation from effects on humans and a potential ecological function is not trivial. (Antkowiak and Gessner 1979; Fricke et al. 2017). In case of the psilocybin topic, for example, despite decades of research about biosynthetic pathways, chemical mechanisms, therapeutic potential, or large-scale production, the fundamental question regarding its precise ecological function still remains unsolved (Lenz et al. 2020). Considering the energetic efforts to synthesize and accumulate secondary metabolites, there must be a strong benefit for the fungal organism to justify the production of these highly complex molecules.
Figure 9.
Examples for chemical defense strategies (red outlined examples caused and causes serious mushroom poisoning in the past and present).
A striking example for wound activated defense is the enzymatic conversion of the biologically inactive precursor stearoylvelutinal (85) into the sesquiterpenoids velleral (86) and isovelleral (87) from Lactariusvellereus as a response to injury (Sterner et al. 1985). In addition to their pungent taste, the dialdehydes 86 and 87 exhibit broad spectrum activity including mutagenic activities for isovelleral (87) (Anke and Sterner 1991). Similarly, the enzymatic oxidation of the cyanohydrin ether aleurodisconitril (88) to the aleurodiscoester (89) probably causes the release of hydrocyanic acid to protect the fruiting bodies of the crust fungus Aleurodiscusamorphus against feeding predators (Kindler and Spiteller 2007).
As recently shown for Mycenarosea, interactions involving chemical defense between ‘prey’ and predators can be highly sophisticated and complex. Using formaldehyde (90) in a constitutive defense mechanism against Spinellusfusiger, M.rosea is able to protect the fruiting bodies – to some degree – from infestation with this mycoparasite (Himstedt et al. 2020). On the other hand, S.fusiger is producing large quantities of gallic acid (91) as a counterdefense agent, which reacts with amino acids and formaldehyde to Mannich adducts to detoxify the formaldehyde (90).
Further examples for the production of secondary metabolites as antimicrobial weapons are the antifungal strobilurins (26, 84) (Anke 1995), the anti-staphylococcal calopins, such as 8-deacetylcyclocalopin B (92) from Caloboletusradicans (Tareq et al. 2018), or the nematicidal laccanthrilic acid B (93) from several Laccaria species (Schrey et al. 2019b). Most of these studies are based on the evaluation of the compound against a panel of bacteria and fungi using concentrations that are matching the ecological concentrations. Noteworthy, physiologically relevant concentrations were shown to act as an interspecies signal rather than a toxin as reported in a study examining dose-dependent effects of phenazine-derived metabolites in co-culture biofilms of Pseudomonasaeruginosa and Aspergillusfumigatus (Zheng et al. 2015). While high concentrations of the antimycotics were toxic for the fungus, moderate concentrations affected fungal sporulation and development via oxidative stress regulation.
Figure 10.
Further examples of the production of secondary metabolites as microbial weapons.
Beside chemical defense mechanisms, fungi are creative artists in establishing symbiotic interactions or conquering habitats by actively attacking other fungi, plants, or insects (Spiteller 2015). For the latter, based on their pathogenic or parasitic lifestyle, these fungi often use cell wall decaying enzymes to infect the host together with toxic compounds to degrade or to handle its chemical defense. Well-investigated examples of the correlation of chemistry and ecological function of secondary metabolites are fungi of the genus Trichoderma, commonly encountered as mycoparasites and endophytes, producing different antibiotics such as harzianolide (94), harzianopyridone (95), trichothecenes, peptaibols or gliotoxin (96) (Brian and Hemming 1945; Bell et al. 1958; Dickinson et al. 1989; Cai et al. 2013; Proctor et al. 2018; Marik et al. 2019) and Sepedoniumchrysospermum, a necrotrophic mycoparasite that infects the fruiting bodies of Boletaceae, producing sepedonin (97), (-)-sclerotiorin (98), and (-)-chrysodin (99) (Wright et al. 1970; Closse and Hauser 1973).
In contrast to this predatory behavior, fungi also frequently form mutualistic relations with various organisms. For ectomycorrhizal associations between plants and Basidiomycota in particular, the mycorrhization of the roots is essential for the survival of approximately 6000 species in 145 genera of land plants (Hyde et al. 2019). Despite the fact that ectomycorrhizal associations have been acknowledged for more than one hundred years, little is known about the chemistry, particularly the signaling molecules that initiate mycorrhizal formation, regulation of the nutrient cycle, and interaction with other organisms such as soil bacteria and fungal endophytes (Spiteller 2015). During the pre-colonization phase of the ectomycorrhizal formation, lateral root development is stimulated through non-host specific volatile organic compounds (VOC) acting as chemical messengers to achieve a recognition of both partners (Felten et al. 2009; Ditengou et al. 2015). In case of the basidiomycete Laccariabicolor, the phytohormone indole-3-acetic acid (100), considered to be one of the main drivers for root formation, could be observed alongside with sesquiterpenes, such as (-)-thujopsene (101) (Ek et al. 1983; Ditengou et al. 2015).
Other symbiotic interactions are those of plants and endophytic fungi, where the fungal organism lives inside plant tissue and is part of the microbial community without causing negative effects to the host (Porras-Alfaro and Bayman 2011; Raimi and Adeleke 2021). In this mutualistic relationship, the main paradigm in regard to secondary metabolite research is depicted by the endophytic fungus producing potent bioactive secondary metabolites for plant protection. This assumption is the key principle for the and development of endophytes for biocontrol to protect plants against pathogens. A recently reported and discussed, promising example might be the use of Hypoxylonrubiginosum and related taxa against the ‘Ash Dieback’, a chronic disease of the European ash (Halecker et al. 2020; Pourmoghaddam et al. 2020). Producing the antifungal compound phomopsidin (102) and its derivative (103) in the presence of the pathogen, Hypoxylonrubiginosum species could contribute to fencing growth of the invasive Hymenoscyphusfraxineus that compromises European forestry.
Continuous development of Omics associated technology is aiding this line of research. Defined as a nonselective, comprehensive, and rapid analytical tool, metabolomics have accelerated modern approaches in chemical ecology and in discovery of novel bioactive metabolites. Based on metabolic profiling of complex biological matrices, metabolome analyzes allow laying focus on intra- and interspecies interactions via hyphenated LC-MS and LC-NMR applications for identification and quantification of metabolites. In the field of comparative metabolomics, chemical profiles are evaluated under different conditions (e.g. an axenic culture versus a stimulated culture) to uncover differences. A promising example of this comparative approach is the discovery of fumigermin (104), a novel germination inhibitor of Streptomycesrapamycinicus (Stroe et al. 2020). To identify differences as a consequence of fungal-bacteria interactions, the metabolomes of monocultures and co-cultures of Aspergillusfumigatus and S.rapamycinicus were profiled. This revealed the presence of large amounts of 104 in bacterial-fungal co-cultures, while the axenic fungal culture contained fumigermin (104) only in traces. Therefore it can be concluded that an unknown mediator associated with S.rapamycinicus triggered activation of the weakly expressed biosynthetic gene cluster of 104 in A.fumigatus. Owing to the fact that both organisms share the same habitat, the production of the bacteria-specific germination inhibitor fumigermin (104) is considered as a fungal defense system against its bacterial competitor.
Novel fungi and novel habitats lead to novel chemistry
The discovery of novel secondary metabolites with interesting biological activities is often linked with the use of under- or unexplored species (Hyde et al. 2018). Besides untapped or difficult to handle taxa (e.g. slowly growing organisms, mycorrhizal fungi, rare taxa), sophisticated producers are frequently reported from unchartered geographical regions (e.g. the sub- or tropical regions) or unexplored habitats (e.g. fungi isolated from animal dung, particularly from herbivorous mammals). Investigations on organisms from the tropical Kenyan rain forest resulted in the discovery of many new species together with a variety of novel structurally diverse secondary metabolites. Microporenic acids (105–106), isocitric acid derivatives with polyisoprene moieties from genera of the Polyporaceae, namely Microporus sp. and Lentinuscf.sajor-caju, have been isolated as promising inhibitors of Staphylococcusaureus biofilms with effects within a non-lethal range for the opportunistic pathogen (Chepkirui et al. 2018a; Zeng et al. 2024; Fig. 11). When treated in combination with vancomycin and gentamycin, microporenic acid I (106) was able to enhance the efficacy of the established antibiotics in biofilms, indicating potential applications in combinatorial therapy. On the other hand, the isolation of several novel core structures from a new tropical Heimiomyces sp. is an outstanding example of the structural diversity and complexity that can prevail in a single strain. Recently, heimiocalamenes, heimiomycins (107), bis-heimiomycenes (108) or heimionones (109) – with a new meroterpenoid scaffold – were discovered via a study of this strain, which produced entirely different metabolite profiles in different culture media (Pfütze et al. 2023a, 2023b), with fermentation times of up to 7 months in solid state medium. Another example depicts the nematicidal phelligridin L (110), reported from a hitherto undescribed African species of the genus Sanghuangporus belonging to the Inonotusluteus complex, a complex otherwise well-known from Asian countries (Chepkirui et al. 2018b). Its Asian members have elaborately been studied for their chemical constituents and pharmaceutical properties due to their usage as medicinal mushrooms (De Silva et al. 2013; Cheng et al. 2019). The discovery of phelligridin L (110) from an African Sanghuangporus sp. underpins the potential of discovering novel secondary metabolites from undescribed species or unexplored regions. Another compelling and rewarding example of innovative chemistry derives from the rare temperate mushroom Rhodotuspalmatus. Here, the unique meroterpenoid rhodatin (111) and its strong antiviral activity against hepatitis C virus together with several other new sesquiterpenoid scaffolds (112–113) were discovered during a first study on its secondary metabolism (Fig. 13, Sandargo et al. 2019b, 2019c). Remarkably, rhodocorane scaffolds 112 and 113, amongst others, were previously only known as intermediates from synthetic routes and not described as occurring in nature. Further recent examples for new chemistry from Basidiomycota are summarized in the review by Sum et al. (2023) and therefore will not be discussed in detail here.
Figure 11.
Examples for novel metabolites from under- and unexplored sources.
Coprophilous fungi represent another promising source for chemical innovation and novel secondary metabolites. Coprophilous fungi are dung-colonizing organisms and may belong to the orders Eurotiales, Hypocreales, Onygenales, Pezizales, Pleosporales, Microascales, Sordariales, or Xylariales (Bills et al. 2013). Because of spending their complete life cycle in the dung, they are highly adapted towards their environment. Within these microcosms, coprophilous fungi are constantly challenged by a highly competitive community: Due to niche overlap with other bacteria, protists, invertebrates, the mammalian digestive system, and other fungi, they have to compete in a nutrient-rich substrate ensuring their survival and reproduction. Even if competing successfully, sought-after assimilated nutrients are now concentrating in fungal hyphae, evoking the attack of predators and parasites. Stimulated by the surrounded biodiversity, coprophilous fungi are prolific producers of numerous antimicrobial compounds and robust secondary metabolite arsenals as reviewed by Bills et al. (2013). Examples are the production of the tetracyclic diterpenoid sordarin (114) and derivatives thereof with strong antifungal activities from Podosporapleiospora isolated from rabbit pellets (Weber et al. 2005), the discovery of the sesquiterpenoids hypocoprins A-C (115–117) from Hyprocoprarostrata from horse dung with moderate antibacterial effects against Gram-positive germs (Jayanetti et al. 2015), or the benzophenones delicoferones (118–119) from Delitschiaconfertaspora from rock hyrax dung (Jayanetti et al. 2017). Studies on the coprophilous community have demonstrated that the dung habitat is characterized by a rich density of microfungi with highly significant differences regarding their seasonal occurrence, latitudinal gradient, and preferred substrate composition (Richardson 2001). Coprophilous fungi also live in strong competition with other fungi, as well as with bacteria and invertebrate animals. Compared to the high biodiversity that can be found in this habitat, along with the relatively high hit rate for novel compounds in the few studies that have so far been conducted, dung-inhabiting fungi clearly constitute an underexplored source for the discovery of new bioactive secondary metabolites (Bills et al. 2013; Charria-Girón et al. 2022).
A well-developed secondary metabolism is, however, not spread throughout all fungal groups and seems to be reserved only to specific evolutionary lineages, with the Ascomycota and Basidiomycota featuring the most prolific sources (Bills and Gloer 2016). In the next section, we want to highlight a brief selection of well-studied groups and species of these two phyla.
Notable examples from Ascomycota and Basidiomycota
The Ascomycota are arguably the most intensely studied phylum in respect to their biodiversity among the kingdom of fungi (Fig. 13). Natural products isolated from these fungi have been extensively reviewed. Hence, the reader is directed towards reviews covering the most species-rich classes Eurotiales within the Eurotiomycetes (see also taxonomical tool section; Lan and Wu 2020), the Hypocreales (Wei and Wu 2020; Zhang et al. 2020; Kuephadungphan et al. 2021), Xylariales (Helaly et al. 2018; Becker and Stadler 2021; Kuephadungphan et al. 2021), Amphisphaeriales (e.g. Wang et al. 2012; Ortega et al. 2021), Diaporthales (Chepkirui and Stadler 2017), Sordariales (Charria-Girón et al. 2022) from the Sordariomycetes and Lecanoromycetes (Jahn et al. 2017; Keller 2019) as well as the Dothideomycetes (Stergiopoulos et al. 2013; Muria-Gonzalez et al. 2015). An example of a drug lead developed from this group is the nematicide emodepside (118) (Willson et al. 2003) which is a semisynthetic derivative of PF1022A (119), a cyclooctadepsipeptides produced by Rosellinia spp. (Wittstein et al. 2020; Fig. 12). Other compounds such as nodulisporic acids (120–122) and sordarin (112) are leads in development for their antiparasitic and antifungal properties, respectively.
Figure 12.
Examples for secondary metabolites isolated from Ascomycota.
Other well-known and extensively used compounds in science comprise the cytochalasans (12–14) produced by various genera of ascomycetes, for which well over hundred different structures are known. The best studied examples in regard to their bioactivity are cytochalasins B and D (13–14), which will be summarized later. A recently published review also highlighted the importance of international collaborative efforts to cartograph the enormous wealth of extractable secondary metabolites, exemplified by Thai ascomycete mycodiversity (Kuephadungphan et al. 2021).
The Basidiomycota include most of the mushroom-forming fungi (Fig. 15) and are the second largest division in the kingdom Fungi next to the Ascomycota (Wijayawardene et al. 2020). The structural variety of secondary metabolites derived from Basidiomycota (Sandargo et al. 2019a) and their complex repertoire of natural product biosynthesis has recently been reviewed (Gressler et al. 2021). The secondary metabolism of their mycelia and corresponding fruitbodies is complementary, and many Basidiomycota are prolific producers of secondary metabolites. In natural habitats, both parts have different ecological functions (Spiteller 2008). While the mycelia compete with other organisms for nutrition and space, the fruiting bodies are mostly short-living phenomena that ensure the reproduction of the producing fungus. However, the few studies available demonstrate that the corresponding mycelial cultures do at least not overproduce the constituents of the fruiting bodies. For instance, in the case of the saprotrophic genus Hericium, the meroterpenoids of the hericenone type (e.g. Wittstein et al. 2016) are prevailing in the fruiting bodies, while the cultures predominantly produce cyathane type diterpenoids (Rupcic et al. 2018). A recent study embarking on two of the few species of the Boletaceae has shown that it is possible to produce the colorful pigments (Fig. 3), such as xerocomic acid (43), variegatic acid (44), or variegatorubin (45), that are generally prevailing in the fruiting bodies of these fungi also in mycelial culture (Chuankid et al. 2020).
Figure 15.
Morphological diversity of Basidiomycota: Clavulinopsis sp. (A), Armillariamellea (B), Psilocybecyanescens (C), Hygrocybeconica (D), Gliophoruspsittacinus (E), Hohenbuehelia sp. (F), Geastrummichelianum (G), Mycenapseudocorticula (H), Rubroboletussatanas (I), Cortinariusviolaceus (J), Chondrostereumpurpureum (K), Rhodotuspalmatus (L), Laetiporussulphureus (M). Photos: Harry Andersson (C, K, M); Benjarong Karbowy-Thongbai (F); Torsten Richter (B, D, E, H–J), Hans Pfeiffer (A); Hedda Schrey (G); Jürgen Schnieber (L).
In contrast to the “low hanging fruits” from soil-inhibiting molds and bacteria that have been harvested to the benefit of mankind, studying the secondary metabolism of Basidiomycota can be rather demanding. On the one hand, certain promising metabolites such as the anti-biofilm metabolite microporenic acid A (105) (Chepkirui et al. 2018), the potential cytotoxic agent fulvoferruginin (125) (Sandargo et al. 2021), or the antibiotic and antiviral pleurotin type meroterpenoids (126–128) from the nematophagus basidiomycete Hohenbueheliagrisea (Sandargo et al. 2018; Fig. 14) were fairly well accessible with yields of several hundred mg per liter without any extensive need to optimize the production of the wild type strains. On the other hand, there are many other species of Basidiomycota that take up to several months to grow under regular culture conditions, and there are many others that cannot be cultured at present. This is probably due to the fact that these species rely on symbiotic relationships in their natural habitats or have other, hitherto unknown nutrient requirements. The polypore of the genus Amylosporus are associated with grasses (Campi et al. 2017), and took almost 3 months of growth in liquid culture for the production of amylosporanes (129) and the antibacterial agents colletorin B (130) and colletochlorin B (131) (Matio Kemkuignou et al. 2022). Conceivably, systematic biotechnological exploitation of Basidiomycota can hence be even more difficult than for other Ascomycota due to their slow growth or low production titers.
Figure 14.
Examples for secondary metabolites from Basidiomycota.
Secondary metabolites as taxonomical tools in the systematics of fungi
Secondary metabolites can occur in the form of conspicuous pigments, where they can exhibit useful properties for chemotaxonomical approaches (summarized by Frisvad et al. 2008). This system has successfully been used to reorder the systematics of species, genus, or even families in the Kingdom Fungi, both in the division Basidiomycota, particular in the Boletales (Gill and Lally 1985; Winner et al. 2004; Bresinsky 2014) and in the Ascomycota (e.g. in Aspergillus, Penicillium and the Hypoxylaceae). The key concept lays in the combination of different phenotypic characters, such as morphology, chemical constituents and multilocus genetic data in polyphasic approaches.
Interest to achieve metabolic profiling of Aspergillus spp. and Penicillium spp. (a genus which was eventually segregated into the genera Penicilliums. str. and Talaromyces, also based on chemotaxonomic criteria) is strongly linked to their importance as mycotoxin producers as both food related molds and human pathogens and due to their widespread usage as biotechnological workhorses for the production of enzymes, citric acid and in food industry. Domesticated Aspergillus species feature, for example, A.niger, A.flavusvar.oryzae and A.sojae. The taxon A.niger is classified in section Niger, while A.flavusvar.oryzae and A.sojae are classified in section Flavi, two sections known to feature potent mycotoxin producers. Hence, metabolic profiling and a thorough taxonomic characterization may contribute towards minimizing the risk of using mycotoxigenic fungal strains in industrial application (reviewed by Houbraken et al. 2014 and Frisvad et al. 2018). In the clinical context, it is understandably of high relevance to reliably tell if an Aspergillus infection coincides with production of the potent aflatoxins (132–135) or immune suppressive gliotoxins (96). Knowledge of these traits has serious implications for the prospect of treatment options for patients. Metabolic profiling of Aspergillus, but also Penicillium spp. by HPLC coupled to an UV-Vis detection system was shown to be feasible for chemotyping of isolated cultures in 1989 by Frisvad and turned out to be a highly consistent phenotypical character for taxonomic purposes (taxonomic overview by Houbraken et al. 2020). The enormous wealth of secondary metabolites (termed extrolites in Aspergillus and Penicillium taxonomy, as being ‘outward’ directed chemicals) described for the different systematic sections is in the process of being reviewed extensively (Frisvad and Samson 2004; Samson et al. 2004; Frisvad et al. 2007; Nielsen et al. 2009; Frisvad and Larsen 2015, 2016; Kocsubé et al. 2016; Frisvad et al. 2019; Ráduly et al. 2020) in toxicological and taxonomic contexts. Among the 807 secondary metabolites described until 2017 (Vadlapudi et al. 2017), many substance classes emerged as being taxonomically informative to improve or support species descriptions in combination with other observations in polyphasic approaches. This was last assessed comprehensively by Kocsubé et al. (2016) to settle the monophyly of Aspergillus segregated from Penicillium.
Strong public interest is focused on their relevance as mycotoxin producers, which account for huge economic losses by food spoilage, but also for public health due to contaminated food (Ráduly et al. 2020). The most important toxins from Aspergillaceae are the aflatoxins (especially of type B1, B2, G1 and G2, 132–135). Ochratoxin A (136) and gliotoxin (96) are also common in Aspergillus, while fumonisins (137–139) occur occasionally in Aspergillus but mostly in Fusarium spp. and sterigmatocystin (140) is widespread in Aspergillus but even occurs in many other genera like Chaetomium (Rank et al. 2011). Aflatoxins (especially produced by AspergillussectionFlavi) are carcinogenic and can lead to death in acute intoxication events (Dhanasekaran et al. 2011). Ochratoxin A (136) (present in both Aspergillus and Penicillium) has a wide range of toxic effects on the human body, while carcinogenic properties are being hypothesized as it can induce cancer in animal model systems (Heussner et al. 2015). Gliotoxin (96), typically produced by Aspergillussect.Fumigati, is often referred to as a virulence factor, playing an important role in clinical infections, suppressing the host’s immune response. However, not every producing strain has also been shown to possess human pathogenic tendencies (Corrier et al. 1991; Frisvad and Larsen 2016). Sterigmatocystin is biosynthetically very similar to aflatoxins and can even be converted when an aflatoxin producing competent and deficient Aspergillus co-colonize the same substrate (EFSA 2013). While still being toxic, its carcinogenic potential is far lower than that of aflatoxins (132–135; Fig. 16). Fumonisins (137–139) are also well known to exert carcinogenic potencies and to induce developmental disorders like defects in the neural tube and toxicity against kidney and liver (Nair 1998). Patulin (141) is another well-known mycotoxin, which typically occurs in Penicilliumexpansum but occasionally also occur in other Penicilia and even Aspergilli (subgenera Aspergillus, Cremei and Fumigati). It can frequently be found in apple juice derived from moldy apples (Frisvad 2018). Yeasts, however, are able to break down the compound during fermentation (Yu et al. 2007), making the ingestion of cider comparably safe (disregarding the chance of alcohol poisoning). Other more broadly distributed secondary metabolites are the xanthocillins (142–144) and terphenyllins (145–146), which are evenly distributed among all subgenera of Aspergillus.
Figure 16.
Examples for chemotaxonomic markers for Ascomycota.
A chemotaxonomic classification also helped to resolve many taxonomical issues in the important xylarialean family Hypoxylaceae. Here, a polyphasic approach combining chemical, genetical and a morphological analysis of environmental samples from saprobically growing teleomorphic structures of genera like Annulohypoxylon (Kuhnert et al. 2017), Daldinia (Stadler et al. 2014) and Hypoxylon (Kuhnert et al. 2014; Sir et al. 2016) helped to settle many incongruent classifications based on morphological data alone. Members of the Hypoxylaceae often contain large amounts of secondary metabolites in their wood-inhabiting stromata, which may even exceed 10% of the total dry biomass (Stadler and Fournier 2006; Stadler et al. 2007). These compounds are mostly azaphilones (e.g. rubiginosins (147–148), mitorubrins (54) and daldinins (149–152), but also compounds primarily associated with younger growth stages (e.g. cytochalasins 12–14). While these compounds proved to be of value as chemical markers, their precise role in nature is comparably poorly understood. In the case of rubiginosin C (148) it was found that the fungal pigment is able to interfere with the formation of biofilms and the yeast-to-hyphae transition of Candidaalbicans and Candidozymaauris. This morphological change is an important driver for the establishment of stable and resistant biofilms on surfaces (Zeng et al. 2023), a potential indicator for its ecological function. Nevertheless, most of the compounds found in stromal extracts cannot be produced by fermentation. Hence, availability is currently restricting biotechnological exploitation (Becker and Stadler 2021). However, as the genomic era is more and more introduced into fungal secondary metabolite research, comparative genomic studies may enable exploiting chemotaxonomical information by linking compound production to the presence of specific BGCs detectable in different phylogenetic clusters and improve systematics by using phylogenomics, in turn again fostering the identification and prediction of biosynthetic gene clusters in sequenced genomes (Kuhnert et al. 2021; Wibberg et al. 2021).
Other approaches include the analysis of the protein composition viaMALDI-TOF, used as a rapid identification method in a clinical context, which is very helpful for diagnostics of human pathogens and far superior over the ITS barcoding approaches that often have little discriminatory power (Bader 2017; Becker et al. 2019). Its versatility and complementarity have recently been demonstrated for the zoonotic fungal pathogen species complex Trichophyton, where its diagnostic feasibility was validated by a detailed phenotypical study including morphology, genetical information and microsatellite marker analysis (Čmoková et al. 2020). Notably, MALDI-TOF is a proteomics-based technique that has nothing to do with secondary metabolite analysis. In a recent study on Pyrenopolyporus from Thailand, MALDI-TOF was also found suitable to resolve a complicated species group (Wongkanoun et al. 2023). However, the effort to create the analytical data after standardized cultivation and analytics hitherto was found to be much more strenuous than the more conventional approach using morphology, molecular phylogeny and HPLC profiling, and it requires availability of viable cultures. Therefore we strongly advise against its broad use outside the medical field.
Secondary metabolites as biochemical tools
While only few fungal metabolites have made it to the pharmaceutical market or inspired the development of synthetic drugs, the number of biosynthetic tool compounds that are valuable in biochemistry, cell biology, physiology and related disciplines is much higher. Not every natural product has optimal chemical and physical characteristics to serve as a potential new drug. However, once the mode of action is characterized, secondary metabolites can become attractive tools to track or interfere with specific biological processes.
Wortmannin (153; Fig. 17), for example, is a furanosteroid first isolated from Penicilliumwortmannii (now Talaromyceswortmannii) as antifungal agent (Brian et al. 1957). Organismic cytotoxic hemorrhagic effects on rats were noticed by Abbas and Mirocha (1988). In studies involving neutrophils, wortmannin (153) and related compounds were shown to inhibit the respiratory burst, an immunological response to phagocytosis generating vast amounts of reactive oxygen species to kill-off taken up particles (Baggiolini et al. 1987). Exploration of the signal cascade responsible for the neutrophil response indicated the involvement of two G-protein mediated cascades (Dewald et al. 1988), which led to the description of wortmannin (153) as a phosphatidylinositol 3-kinase (PI3K) inhibitor in the low nanomolar range (Arcaro and Wymann 1993). Its selectivity for the PI3K enzyme was later assessed by Powis et al. (1994) and its mode of action elucidated by Wymann et al. (1996), however, Liu et al. (2005) could show that the mammalian polo-like kinase (PLK) poses an additional cellular target, undermining the previous thought of wortmannin representing a selective inhibitor of the PI3K. This finding gave the compound implications as an anti-cancer agent, as PLK has been shown to be overexpressed in various cancers (Strebhardt 2010), in addition to blocking the signal transduction to enable DNA repair in response to DNA damage in yeast (Zewail et al. 2003). However, compound stability issues limited its potential use as reviewed by Wipf and Halter (2005). Advances in drug delivery systems assessed and discussed by Karve et al. (2012) may clear the way for its potential use as a radiosensitizer if its systemic toxicity can be handled, however, only time will tell if this new direction can spark new interest in exploring its capacities in the medicinal context. Nevertheless, this knowledge was of great help to access the role of PI3K not only in mammals, but also in yeast and plants, where it was used to better understand and study vesicle trafficking (Zewail et al. 2003; Wang et al. 2009; Takáč et al. 2012; Liu et al. 2020b).
Figure 17.
Examples of secondary metabolites from fungi which are used as biological tools in science.
Another broadly applied secondary metabolite is brefeldin A (154) formerly described as decumbin, cyanein, ascotoxin, synergisidin or nectrolide), a macrocyclic lactone exhibiting antiviral, cytotoxic, phytotoxic and cancerostatic effects, as well as effects on fungal morphogenesis (reviewed by Betina 1992). First isolated as decumbin (Singleton et al. 1958) from Penicilliumdecumbens and later formally described as brefeldin A (154) from P.brefeldianum (Härri et al. 1963; Sigg 1964; Singleton and Bohonos 1964), it is best known for its inhibitory effect on the protein sorting machinery associated with the golgi apparatus in animal and plant cells (reviewed by Nebenführ et al. 2002). Brefeldin A (154) became of particular importance due to its ability to block intracellular transport (Misumi et al. 1986) and cause disassembly of the Golgi apparatus and its fusion with the endoplasmatic reticulum. This ultimately led to the description of the retrograde membrane trafficking pathway from the cis- side of the Golgi back to the endoplasmatic reticulum (Lippincott-Schwartz et al. 1989; Klausner et al. 1992). Brefeldin A (154) thus played a major role in deciphering membrane traffic and secretion pathways (reviewed by Pelham 1991; Klausner et al. 1992; Chardin and McCormick 1999), far before its intracellular target has been identified (Arf guanine nucleotide exchange factors, GEFs; see Niu et al. 2005). Since then, it is now well defined as inhibitor of coating-protein assembly enabling the formation of vesicles and most commonly discussed in the context of Arf-GEF interaction (reviewed by Jackson 2018; Walton et al. 2020).
The last example comprises phalloidin (81) from Amanitaphalloides and cytochalasins (e.g., 12–14), which frequently occur in the orders Eurotiales, Sordariales and Xylariales (Scherlach et al. 2010; Becker and Stadler 2021; Charria-Girón et al. 2022), amongst others. These inhibitors are well known to interfere with the eukaryotic actin cytoskeleton but differ in their mode of action. Phalloidin (81) acts as a stabilizer of filamentous actin structures, while cytochalasins have been described to inhibit F-actin polymerization among other actin and non-actin related effects (Copper 1987; Sampath and Pollard 1991). Phalloidin (81) has mostly been used in its early days to study the role of a disrupted actin cytoskeleton due to excessive stabilization, which made it a very valuable tool to study actin structures back when the role of actin itself was not conclusively established (cf. Wehland et al. 1977). Later, its tight and rather selective association with polymerized actin was exploited to develop an easy-to use fluorescent probe to visualize F-actin structures, which gave rise to an alternative actin staining tool besides the use of actin antibodies for cell biologists (Wulf et al. 1979; reviewed by Faulstich et al. 1988), even before phalloidins’ precise biochemistry and mechanism of action was comprehensively understood (Coluccio and Tilney 1984; Vandekerckhove et al. 1985; Barden et al. 1987; Sampath and Pollard 1991). Even though it was known for a long time, recent developments still increased our understanding of the chemistry of phalloidin (81) (Yao et al. 2019). Nevertheless, its role in microscopical high-end super resolution imaging will at some point likely be replaced by other techniques that are currently in development (cf. Mazloom-Farsibaf et al. 2021). Cytochalasins are best known for their interference with actin polymerization by inhibiting monomer addition (12–14), but also other cellular targets have been described (see Kapoor et al. 2016). They are specifically used in literature to study the role of active (or inactivated) actin polymerization in cellular movement or actin associated processes. From the hundreds of hitherto described cytochalasan related structures (Zhu et al. 2021), cytochalasins B and D (13–14) can be highlighted as the most frequently encountered molecules (cf. Cooper 1987; Van Goietsenoven et al. 2011; Lambert et al. 2023). In the early days of actin and motility research, cytochalasins (12–14) played a major role in attributing filament growth in the neuronal growth cone to actin. Usage of cytochalasins to investigate and inhibit contractile ring formation during cell division led to an analogous conclusion, however, a surprising one at that time, that nuclear division was not inhibited. This simultaneously demonstrated the independence of nuclear and cell division from one another, summarized by Peterson et al. (2002) as hallmark achievements using these compounds. Actin as cytochalasan’s prominent cellular target was only comprehensively described later (Schroeder 1970; Spudich and Lin 1972; Ohmori et al. 1992). Apart from detailed studies on selected compounds, the impact of chemical differences in the core cytochalasan structure is not comprehensively understood (Scherlach et al. 2010), despite several studies attempting to gain knowledge by screening several cytochalasins (Yahara et al. 1982; Van Goietsenoven et al. 2011; Kretz et al. 2017). There is much more to learn about potential fields of uses, as recent papers show much potential in modifying and outlining differential effects for other cell biological (or drug-related) applications (Skellam 2017; Wang et al. 2019a; Moussa et al. 2020; Wang et al. 2020; Lambert et al. 2021). For further reading, we would like to direct the inclined reader to our recent review on the paper, where we have summarized cytochalasans’ impact on actin filament remodeling in more detail (Lambert et al. 2023).
Synthetic biology approaches to natural product chemistry
Recent studies in the Genomics era have revealed that fungal genomes contain an unexpected number of BGC that does not match the number of secondary metabolites previously reported from these organisms. This phenomenon is usually referred to as the presence of “silent” metabolic pathways that need to be activated (Keller 2019). We here just mention some prominent examples of how researchers have tried to tackle this challenge. This can be achieved by molecular genetic manipulations, such as gene deletion (knockouts) or by expression of a set of BGC-associated genes in a different organism (heterologous gene expression, Krappmann 2014; Lazarus et al. 2014; He et al. 2018). This concurrently allows the functional dissection of associated genes and enzymes involved. Challenges involve the selection of suitable host strains that allow the correct expression of target genes and that produced compounds are non-toxic for the host (Markina et al. 2020) – which can sometimes be solved by including additional genes of the associated BGC, as gene clusters were frequently shown to carry self-resistance genes (Keller 2015; Zhang et al. 2021). Moreover, potential chemical modification of host – or even the native producers themselves – concerning enzymatic crosstalk modifying the final product or shunts of intermediates produced during biosynthesis need to be considered (Kjærbølling et al. 2019).
In order to identify and predict BGCs from genomic data, the most frequently used data analysis pipeline is composed of the anti-SMASH (Blin et al. 2023). This analysis suite is continually developed to improve BGC detection, transcription factor and even chemical structure prediction. Notably, gene cluster prediction depends on the quality of the genome sequence data, for which sequencing technology platforms such as offered by Oxford Nanopore or Pacific Biosciences seem to be more than suited for (Kuhnert et al. 2021; Wibberg et al. 2021). With increasing data amount, this also opens avenues to study secondary metabolite gene cluster evolution in larger population sets in unprecedented detail (discussed above for the Hypoxylaceae; Kuhnert and Collemare 2022). Moreover, this will further deepen our knowledge concerning the chemical and enzymatical logic of fungal assembly lines (for several excellent reviews and book, see Cox 2007; Cox 2014; Matsuda et al. 2016; Walsh and Tang 2017; Schor and Cox 2018; Kahlert et al. 2021), at some point maybe enabling the design of completely new natural products.
Exploiting the biosynthetic machinery to increase chemical space: Mutasynthesis and rational design
Synthetic chemists often struggle to recreate the complex chemistry employed by nature from scratch utilizing basic building blocks, but may sometimes be able to utilize similar strategies in a biomimetic fashion (such as for the synthesis of Sch-642305, see Snider and Zhou 2006). Fungal chemistry is also discussed as a tool to further increase chemical diversity by employing their biosynthetic (‘mycosynthetic’) potential in tandem with traditional total- and semi-synthesis (Kahlert et al. 2021). Indeed, further work on honing these strategies will give rise to new possibilities to create new chemistry and facilitate systematical re-creation and diversification of compound synthesis in a rational fashion in heterologous hosts. For a more comprehensive overview on the latter topic, we refer to the recent review by Cox (2024). The next paragraph highlights a few examples for potential application of such strategies.
As discussed further above, biosynthetic routes have frequently been observed to exhibit cross-talk or intersect with other biosynthetic routes, combining building blocks of differing origin in one compound. Well-studied examples can be found among meroterpenoids or NRP-PKs, which show an astonishing degree of versatility (e.g. Wasil et al. 2013; Matsuda and Abe 2016; Skellam 2017). Meroterpenoids, as terpenoids themselves, are comprised of isoprene units of different lengths, which are added to a given backbone (Walsh and Tang 2017). Meroterpenoids are arguably among the most complex natural products synthesized by fungi (Nazir et al. 2021). Recent advances on the biochemistry of meroterpenoid cyclases highlighted a surprising promiscuity of the enzymes involved (Mitsuhashi et al. 2020): Selected cyclases were tested for their substrate scope on a set of natural and unnatural meroterpenoids, which were complemented with further studies on their reaction kinetics. This led to the discovery of 12 new complex unnatural chemical scaffolds. Another example for bioactive meroterpenoids are the melleolides from Armillaria species (Midland et al. 1982; Donelly et al. 1985). We recently studied the secondary metabolism of Armillariaostoyae by varying culture conditions and growth media and were able to isolate in total 38 different derivatives (Fig. 18, Pfütze et al. 2024). Interestingly, dimerized bismelloilides were encountered for the first time. The astonishing diversity of different congeners prompted a search for additional congeners using sophisticated cheminformatics and mass spectrometric tools. This analysis provided evidence for the presence of dozens of additional congeners in the crude extracts of a single strain. If these detectable congeners actually relate to isolatable compounds or merely to unstable intermediates, or spectroscopic artifacts remains to be shown, but a recent study paving the way towards total biosynthesis of melleloides might facilitate this process (Fukaya et al. 2023).
Figure 18.
Melleolide-type meroterpenoids described by Pfütze et al. (2024). Compound numbers correspond to bismelleolide BH-CH and EH (155–157); melleolide linoleate (158); armillarine linoleate (159); melleolide H linoleate (160); 5’-O-desmethylarmillaribin (161); 4-dehydroxyarmillaridin (162); 4-methoxymelleolide H (163); 10-hydroxy-5’-O-methylarmillane (164); 4-dehydroxymelleolide F (165); 10-ketomelleolide E (166); 4,10-dehydroxymelleolide I (167); 4-dehydroxymelleolide I (168); 10-ketomelleolide I (169); 4-acetylarmillaridin (170); melleolide (171); melleolides H and J (172–173); melledonals A and C (174–175); 5’-O-methylmelledonal (176); armillaridin (177), armillarin (178); arnamial (179); dehydroarmillylorselinate (180); melleolides B-E and I (181–185); melledonol (186); 10-dehydroxy-melleolide B (187); 10-oxo-melleolide B (188); A52a (189); 5’-methoxy-6’-choloroarmillane (190); 10-hydroxy-5’-methoxy-6’-chloroarmillane (191); 1-hydroarmillaricin (192). The biosynthesis of melleolides was recently addressed by Fukaya et al. (2023).
In comparison to meroterpenoids, NRP-PK-natural products display a remarkable degree of modularity (as gene clusters encoding PK do in general). Here, a modular PKS produces a backbone comprised of acetyl units of different degrees of saturation (low reducing or highly reducing PKS) which is coupled to amino acids generated in catabolic processes or other unusual peptides synthesized by the same, or even by cross-talk with other NRP gene clusters located in the genome. The promiscuity of a given NRPS in terms of accepting different precursors is an important parameter to enable interventions with the biosynthetic process, which opens the door for precursor-directed secondary metabolite discovery, but also manipulation by synthetic biological approaches (Wasil et al. 2013).
As mentioned previously, gene clusters encoding enzymes accepting a variety of different substrates and thus showing high degrees of promiscuity can serve as valuable exploitable targets for the rational design of compounds to increase chemical space or for specific functionalization. Pyrichalasin H (193; Fig. 19), as one example, is a NRPS-PKS derived natural product first described from Pyriculariaoryzae appearing in different plant pathogens (e.g. Pyriculariagrisea) of the cytochalasan family (Nukina 1987). Cytochalasans are typically comprised of an isoindole moiety, a macrocyclic ring and an amino acid. Well known cytochalasans from Chaetomium spp., called chaetoglobosins (194–195), typically include tryptophan as amino acid, with other common variants incorporating phenylalanine (most cytochalasins) or other amino acids containing hydrophobic side chains. A recent overview of the structural and biosynthetic variety is given by Skellam (2017).
Figure 19.
Chemical structures of pyrichalasin H (193), and chaetoglobosins A and K (194–195).
Recently, progress has been made in the understanding of the biosynthesis of pyrichalasin H (193) in Pyriculariagrisea NI980 (Wang et al. 2019a), where a systematic knockout study on the predicted cluster led to its verification and interestingly, to the production of several new analogues of 193. A later study confirmed that P450 oxidases involved in oxidative tailoring steps from other biosynthetic gene clusters and even other species, can reconstitute the production of the final compound in corresponding knockout strains (Wang et al. 2019b). Not all P450 oxidases could rescue pyrichalasin H (193) production, but instead led to the production of new cytochalasans (12–14), of which three epoxidated variants were described in the discussed study.
While these studies were more focused on the establishment of the biosynthesis and the consequences of disturbances in biosynthetic tailoring steps, Wang et al. (2020) could exploit the apparent promiscuity of the NRPS-PKS adenylation domain. Here, it could be shown by mutasynthesis that feeding halogenated phenylalanine to a knockout missing pyiA, an O-methyl transferase preparing phenylalanine by O-methylation for the biosynthetic incorporation is essential for the fungus to form pyrichalasin H. Wang et al. (2020) exploited these findings by feeding a 4’azido-phenylalanine precursor, assisting in subsequent semisynthetical derivatization of the compound applying click-chemistry with alkines attached to different functional groups for further mechanistic studies. This approach opened a whole toolbox of molecules for different biological and biochemical applications, for which further studies have to follow to explore their effectiveness.
Outlook
In their natural habitats, fungi are productive and prolific producers of ingenious metabolites with potent antimicrobial activities. Modern natural product research should treasure the link between production of secondary metabolites and their ecological context, as fungi behave differently under laboratory conditions lacking external stimuli from their natural habitats. Therefore, more research on innovative strategies is needed in order to challenge fungi to reveal their full chemical arsenal. Nevertheless, determining the ecological and practical function, or biotechnological application of fungi and their natural products can be a daunting task, as a description of their biological target without preliminary knowledge is rather challenging given the predictive capabilities we have available today. Due to the complexity of the task, empirical studies, such as screening for bioactivity in different scenarios and contexts, are imperative to tackle these questions. Since the combinatorial possibilities of potential targets are endless, we strongly recommend to cooperate to cover as much ground as possible. Recently published white papers and reviews by the International Natural Product Sciences Taskforce in high ranking journals clearly show the surging interest in public on natural product research, prompting a tight connection and necessity for biologists and chemists to work together. (Atanasov et al. 2021; Miethke et al. 2021).
Reflecting the work on the description of taxa from underexplored habitats, a high degree of biodiversity has been shown to go hand in hand with chemical diversity. However, fungi which are difficult to maintain in a laboratory environment are posing a serious challenge for systematic natural product description. One strategy is composed of developing techniques focusing on reducing the ratio of previously uncultivable or slow growing fungi, e.g. mycorhizal fungi. The classical approaches to natural product discovery, i.e. systematic screening approaches, fermentation, isolation, and structure elucidation are still key assets for finding novel secondary metabolites. Alternatively, harnessing the genetic resources for the biotechnological production of secondary metabolites by heterologous gene expression out of their encoding gene clusters is a goal which can be aimed for. Scrutinizing the mechanistical rationale of genetic and enzymatic assembly machinery involved in the chemical biosynthesis enables targeted interception by mutasynthesis and opens the way for rationally designing compounds by combinatorial biosynthesis, which will be a key feat to achieve in the future to systematically explore the chemical landscape for further expenditures in biotechnological applications.
Table 3.
Abbreviations used in this text and in natural product discovery research.
Abbreviation | Description | Abbreviation | Description |
---|---|---|---|
Ac-CoA | Acetyl-coenzyme A | MCD | Molecular Connectivity Diagram |
Anti-SMASH | Secondary Metabolite Analysis Shell | MDLC | MultiDimensional Liquid Chromatography |
BGC | Biosynthetic Gene Cluster | ML | Machine Learning |
CASE | Computer Assisted Structure Elucidation | MPLC | Medium Pressur Liquid Chromatography |
CCC | Countercurrent Chromatography | MRM | Multiple Reaction Monitoring |
CD | Circular Dicroism | MTPA | α-methoxy-α-trifluoromethylphenylacetic acid |
C/N ratio | Carbon to Nitrogen ratio | NMR | Nuclear Magnetic Resonance |
COSY | Correlation Spectroscopy | NOESY | Nuclear Overhauser and Exchange Spectroscopy |
CSA | Chiral Solvating Agents | NP | Normal Phase |
DAD | Diode Arrac Detector | NRP | Non-Ribosomal Peptide |
DESI | Desorption Electrospray Ionization | NRPS | Non-Ribosomal Peptide Synthase |
ECD | Electronic Circular Dichroism | NRP-PKs | Non-Ribosomal Peptides coupled to PolyKetides |
EFSA | European Food Safety Authority | 1D / 2D | One Dimensional / Two Dimensional |
EMA | European Medicines Agency | OSMAC | One Strain Many Compounds |
ESI | Electrospray Ionization | PK | Polyketide |
FCC | Flash Column Chromatography | PKS | Polyketide Synthase |
GC | Gas Chromatography | QMS | Quadrupole Mass Spectrometry |
GNPS | Global Natural Products Social Molecular Networking | QTOF | Quadrupole Time of Flight |
HOSE | Hierarchical Organization of Spherical Environments | RDC | Residual Dipolar Coupling |
HSSE | HeadSpace Sorptive Extraction | ROESY | Rotating-frame nuclear Overhauser Effect correlation spectroscopy |
HPLC | High Performance Liquid Chromatography | RP | Reversed Phase |
HILIC | Hydrophilic Interaction Chromatography | SCFE | Super Critical Fluid Extraction |
HR-TOFMS | High-resolution Time of Flight Mass Spectrometry | SEC | Size Exclusion Chromatography |
HTS | High Throughput Screening | S/N | Signal to Noise |
IEC | Ion Exchange Chromatography | SPE | Solid Phase Extraction |
IMS | Ion Mobility Spectrometry | SPME | Splid Phase Micro Extraction |
JBCA | J-Based Configurational Analysis | TLC | Thin Layer Chromatography |
LH-20 | Liquid chromatography medium, properties: Lipophilic Hydrophobic, particle size 20 µm | TOCSY | Total Correlation Spectroscopy |
LR-HSQMBC | Long-Range Heteronuclear Single Quantum Multiple Bond Correlation | UDB | Universal NMR database |
LR-selHSQMC | Long-Range selective Heteronuclear Single Quantum Multiple Bond Correlation | UHPLC | Ultra High Performance Liquid Chromatography |
MALDI | Matrix-Assisted Laser Desorption/Ionization | VOC | Volatile Organic Compounds |
Acknowledgements
We are grateful to Jörg Albers, Harry Andersson, Lillibeth Chaverra-Muñoz, Henrik-Alexander Christ, Bettina Haberl, Hans Pfeiffer, Benjarong Karbowy-Thongbai, NBT Plant Microbe Bank (National Biobank of Thailand, National Center for Genetic Engineering and Biotechnology; Sarunyou Wongkanoun), Plant Microbe Interaction Research Team, National Center for Genetic Engineering and Biotechnology, Thailand (Jennifer Luangsa-ard, Artit Khonsanit); Torsten Richter, Nina Sandmann, Jürgen Schnieber, Frank Surup and Cobus Visagie for providing photos. Fig. 6 was created with BioRender.com. Funding from the Deutsche Forschungsgemeinschaft (DFG) for the research network “CytoLabs – Systematic Investigation and Exploitation of Cytochalasans” (DFG-FOR5170) is gratefully acknowledged. This research benefited from funding by the European Union’s Horizon 2020 Research and Innovation Program (RISE) under the Marie Skłodowska-Curie grant agreement [101008129]; and Project Acronym “MycoBiomics”. We also gratefully acknowledge the input of Cedric Pearce for giving us valuable feedback on the previous version of this work, which was initially intended to be a book chapter.
Citation
Schrey H, Lambert C, Stadler M (2025) Fungi: Pioneers of chemical creativity – Techniques and strategies to uncover fungal chemistry. IMA Fungus 16: e142462. https://doi.org/10.3897/imafungus.16.142462
Footnotes
Hedda Schrey and Christopher Lambert contributed equally to this work.
Additional information
Conflict of interest
The authors have declared that no competing interests exist.
Ethical statement
No ethical statement was reported.
Adherence to national and international regulations
Not applicable.
Funding
Funding from the Deutsche Forschungsgemeinschaft (DFG) for the research network “CytoLabs – Systematic Investigation and Exploitation of Cytochalasans” (DFG-FOR5170) is gratefully acknowledged. This research benefited from funding by the European Union’s Horizon 2020 Research and Innovation Program (RISE) under the Marie Skłodowska-Curie grant agreement [101008129]; and Project Acronym “MycoBiomics”.
Author contributions
Alll authors wrote and edited the manuscript.
Author ORCIDs
Christopher Lambert https://orcid.org/0000-0002-1899-8214
Marc Stadler https://orcid.org/0000-0002-7284-8671
Data availability
All of the data that support the findings of this study are available in the main text.
References
- Abbas HK, Mirocha CJ. (1988) Isolation and purification of a hemorrhagic factor (wortmannin) from Fusariumoxysporum (N17B). Applied and Environmental Microbiology 54(5): 1268–1274. 10.1128/aem.54.5.1268-1274.1988 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Adachi K, Kohara T, et al. (1995) Design synthesis, and structure-activity relationships of 2-substituted-2-amino-1,3-propanediols: Discovery of a novel immunosuppressant, FTY720. Bioorganic and Medicinal Chemistry Letters 5: 853–856. 10.1016/0960-894X(95)00127-F [DOI] [Google Scholar]
- Alberts AW, Chen J, et al. (1980) Mevinolin: a highly potent competitive inhibitor of hydroxymethylglutaryl-coenzyme A reductase and a cholesterol-lowering agent. PNAS 77: 3957–3961. 10.1073/pnas.77.7.3957 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Aldridge DC, Armstrong JJ, et al. (1967) The cytochalasins, a new class of biologically active mould metabolites. Chemical Communications 1965: 26–27. 10.1039/c19670000026 [DOI] [Google Scholar]
- Amici AM, Minghetti A, et al. (1969) Production of peptide ergot alkaloids in submerged culture by three isolates of Clavicepspurpurea. Applied Microbiology 18: 464–468. 10.1128/am.18.3.464-468.1969 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Anchel M, Hervey A, Robbins WJ. (1950) Antibiotic substances from basidiomycetes. VII. Clitocybeilludens. PNAS 36: 300–305. 10.1073/pnas.36.5.300 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Andernach L, Sandjo LP, et al. (2016) Terphenyl derivatives from Allantophomopsislycopodina. Journal of Natural Products 79: 2718–2725. 10.1021/acs.jnatprod.6b00690 [DOI] [PubMed] [Google Scholar]
- Anke H, Sterner O. (1991) Comparison of the antimicrobial and cytotoxic activities of twenty unsaturated sesquiterpene dialdehydes from plants and mushrooms. Planta Medica 57: 344–346. 10.1055/s-2006-960114 [DOI] [PubMed] [Google Scholar]
- Anke T. (1995) The antifungal strobilurins and their possible ecological role. Canadian Journal of Botany 73(S1): S940–S945. 10.1139/b95-342 [DOI]
- Anke T. (2020) Secondary metabolites from mushrooms. Journal of Antibiotics 73: 655–656. 10.1038/s41429-020-0358-6 [DOI] [PubMed] [Google Scholar]
- Anke T, Oberwinkler F, et al. (1977) The strobilurins – new antifungal antibiotics from the basidiomycete Strobilurustenacellus. Journal of Antibiotics 30: 806–810. 10.7164/antibiotics.30.806 [DOI] [PubMed] [Google Scholar]
- Anke T, Schramm G, et al. (1984) Antibiotica from Basidiomycetes, XX. – Synthesis of strobilurin A and revision of the stereochemistry of natural strobilurins. Liebigs Annalen 1984: 1616–1625. 10.1002/jlac.198419840910 [DOI] [Google Scholar]
- Anoumedem EGM, Mountessou BYG, et al. (2020) Simplicilones A and B isolated from the endophytic fungus Simplicilliumsubtropicum SPC3. Antibiotics 9: 753. 10.3390/antibiotics9110753 [DOI] [PMC free article] [PubMed]
- Antecka A, Bizukojc M, Ledakowicz S. (2016) Modern morphological engineering techniques for improving productivity of filamentous fungi in submerged cultures. World Journal of Microbiology and Biotechnology 32: 193. 10.1007/s11274-016-2148-7 [DOI] [PMC free article] [PubMed]
- Antkowiak WZ, Gessner WP. (1979) The structures of orellanine and orelline. Tetrahedron Letters 20: 1931–1934. 10.1016/S0040-4039(01)86882-9 [DOI] [Google Scholar]
- Arcaro A, Wymann MP. (1993) Wortmannin is a potent phosphatidylinositol 3-kinase inhibitor: the role of phosphatidylinositol 3,4,5-trisphosphate in neutrophil responses. Biochemical Journal 293: 297–301. 10.1042/bj2960297 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Asami Y, Jang JH, et al. (2012) Protuboxepin A, a marine fungal metabolite, inducing metaphase arrest and chromosomal misalignment in tumor cells. Bioorganic and Medicinal Chemistry 20: 3799–3806. 10.1016/j.bmc.2012.04.039 [DOI] [PubMed] [Google Scholar]
- Atanasov AG, Zotchev SB, et al. (2021) Natural products in drug discovery: advances and opportunities. Nature Reviews Drug Discovery 20(3): 200–216. 10.1038/s41573-020-00114-z [DOI] [PMC free article] [PubMed] [Google Scholar]
- Avarelo Jr R, Ni Z, Danell RM. (2019) Mass spectrometry and planetary exploration: A brief review and future projection. Journal of Mass Spectrometry 55: e4454. 10.1002/jms.4454 [DOI] [PMC free article] [PubMed]
- D’Atri V, Fekete S, et al. (2019) Recent advances in chromatography for pharmaceutical analysis. Analytical Chemistry 91(1): 210–239. 10.1021/acs.analchem.8b05026 [DOI] [PubMed] [Google Scholar]
- Bader O. (2017) Fungal species identification by MALDI-ToF mass spectrometry. Methods in Molecular Biology 1508: 323–337. 10.1007/978-1-4939-6515-1_19 [DOI] [PubMed] [Google Scholar]
- Baggiolini M, Dewald B, et al. (1987) Inhibition of the phagocytosis-induced respiratory burst by the fungal metabolite wortmannin and some analogues. Experimental Cell Research 169: 408–418. 10.1016/0014-4827(87)90201-1 [DOI] [PubMed] [Google Scholar]
- Bailey AM, Alberti F, et al. (2016) Identification and manipulation of the pleuromutilin gene cluster from Clitopiluspasseckerianus for increased rapid antibiotic production. Scientific Reports 6: 1–11. 10.1038/srep25202 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Barden JA, Miki M, et al. (1987) Localizsation of the phalloidin and nucleotide-binding sites on actin. European Journal of Biochemistry 162: 583–588. 10.1111/j.1432-1033.1987.tb10679.x [DOI] [PubMed] [Google Scholar]
- Barnes EC, Kumar R, Davis RA. (2016) The use of isolated natural products as scaffolds for the generation of chemically diverse screening libraries for drug discovery. Natural Product Reports 33: 372–381. 10.1039/C5NP00121H [DOI] [PubMed] [Google Scholar]
- Bauer A, Brönstrup M. (2014) Industrial natural product chemistry for drug discovery and development. Natural Product Report 31: 35. 10.1039/C3NP70058E [DOI] [PubMed]
- Bayram Ö, Krappmann S, et al. (2008) VelB/VeA/LAeA complex coordinates light signal with fungal development and secondary metabolism. Science 320(5882): 1504–1506. 10.1126/science.1155888 [DOI] [PubMed] [Google Scholar]
- Beaumont PC, Edwards RL, Elsworthy GC. (1968) Constituents of the higher fungi. Part VIII. The blueing of Boletus species. Variegatic acid, a hydroxytetronic acid from Boletus species and a reassessment of the structure of boletol. Journal of the Chemical Society C 1968: 2968–2974. 10.1039/j39680002968 [DOI] [Google Scholar]
- Becker K, Stadler M. (2021) Recent progress in biodiversity research on the Xylariales and their secondary metabolism. Journal of Antibiotics 71(1): 1–23. 10.1038/s41429-020-00376-0 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Becker P, Normand AC, et al. (2019) Identification of fungal isolates by MALDI-TOF mass spectrometry in veterinary practice: validation of a web application. Journal of Veterinarian Diagnostic Investigations 31(3): 471–474. 10.1177/1040638719835577 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Becker K, Pfütze S, et al. (2021) Hybridorubrins A–D: Azaphilone heterodimers from stromata of Hypoxylonfragiforme and insights into the biosynthetic machinery for azaphilone diversification. Chemistry – a European Journal 27: 1438–1450. 10.1002/chem.202003215 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bell MR, Johnson JR, et al. (1958) The structure of gliotoxin. Journal of the American Chemical Society 80: 1001. 10.1021/ja01537a065 [DOI]
- Bentley R. (2000) Mycophenolic acid: A one hundred year odyssey from antibiotic to immunosuppressant. Chemical Reviews 100: 3801–3826. 10.1021/cr990097b [DOI] [PubMed] [Google Scholar]
- Benz F, Knüsel F, et al. (1974) Stoffwechselprodukte von Mikroorganismen 143. Mitteilung. Echinocandin B, ein neuartiges Polypeptid-Antibioticum aus Aspergillusnidulansvar.echinulatus: Isolierung und Bausteine. Helvetica Chimica Acta 57: 2459–2477. 10.1002/hlca.19740570818 [DOI] [PubMed] [Google Scholar]
- Besl H, Bresinsky A, et al. (1978) Pilzpigmente. XXXV. 3-O-Methylvariegatic acid and related pulvinic acid derivatives from cultures of Hygrophoropsisaurantiaca (Boletales). Zeitschrift für Naturforschung 33C: 820–825. 10.1515/znc-1978-11-1203 [DOI]
- Betina V. (1992) Biological effects of the antibiotic brefeldin A (decumbin, cynein, ascotoxin, synergisidin): a retrospective. Folia Microbiologica 37(1): 3–11. 10.1007/BF02814572 [DOI] [PubMed] [Google Scholar]
- Bills GF, Gloer JB. (2016) Biologically active secondary metabolites from the Fungi. Microbiology Spectrum 4: 6. 10.1128/microbiolspec.FUNK-0009-2016 [DOI] [PubMed]
- Bills GF, Gloer JB, An Z. (2013) Coprophilous fungi: antibiotic discovery and functions in an underexplored arena of microbial defensive mutualism. Current Opinions in Microbiology 16: 549–565. 10.1016/j.mib.2013.08.001 [DOI] [PubMed] [Google Scholar]
- Bitzer J, Köpcke B, et al. (2007) Accelerated dereplication of natural products, supported by reference libraries. Chimia 61: 332–338. 10.2533/chimia.2007.332 [DOI] [Google Scholar]
- Blin K, Shaw S, et al. (2023) antiSMASH 7.0: new and improved predictions for detection, regulation, chemical structures and visualisation. Nucleic Acids Research 51: W46–W50. 10.1093/nar/gkad344 [DOI] [PMC free article] [PubMed]
- Bode HB, Bethe B, et al. (2002) Big effects from small changes: Possible ways to explore Nature’s chemical diversity. ChemBioChem 3(7): 619–627. [DOI] [PubMed] [Google Scholar]
- Brandão PF, Duarte AC, Duarte RMBO. (2019) Comprehensive multidimensional liquid chromatography for advancing environmental and natural products research. TrAC Trends in Analytical Chemistry 116: 186–197. 10.1016/j.trac.2019.05.016 [DOI] [Google Scholar]
- Bresinsky A. (2014) Ants, plants and fungi: A view on some patterns of interaction and diversity. In: Lüttge U, Beyschlag W, Cushman J (Eds) Progress in Botany (Genetics – Physiology – Systematics – Ecology), Vol 75, 3–54. Springer, Berlin, Heidelberg. 10.1007/978-3-642-38797-5_1 [DOI]
- Breton RC, Reynolds WF. (2013) Using NMR to identify and characterize natural products. Natural Product Reports 30: 501–524. 10.1039/c2np20104f [DOI] [PubMed] [Google Scholar]
- Brian PW, Hemming HG. (1945) Gliotoxin, a fungistatic metabolic product of Trichodermaviride. Annuals of Applied Biology 32: 214–220. 10.1111/j.1744-7348.1945.tb06238.x [DOI] [PubMed] [Google Scholar]
- Brian PW, Curtis PJ, et al. (1957) Wortmannin, an antibiotic produced by Pencilliumwortmanni. Transactions of the British Mycological Society 40(3): 365–368. 10.1016/S0007-1536(57)80033-3 [DOI] [Google Scholar]
- Bucar F, Wube A, Schmid M. (2013) Natural product isolation – how to get from biological material to pure compounds. Natural Product Report 30: 525. 10.1039/c3np20106f [DOI] [PubMed]
- Cai F, Yu G, et al. (2013) Harzianolide, a novel plant growth regulator and systemic resistance elicitor from Trichodermaharzianum. Plant Physiology and Biochemistry 73: 106–113. 10.1016/j.plaphy.2013.08.011 [DOI] [PubMed] [Google Scholar]
- Caldas LA, Soares DMM, et al. (2022) Metabolomics of the wild mushroom Gymnopilusimperialis (Agaricomycetes, Basidiomycota) by UHPLC-HRMS/MS analysis and molecular network. Fungal Biology 126(2): 132–138. 10.1016/j.funbio.2021.11.005 [DOI] [PubMed] [Google Scholar]
- Campi M, Maubet Y, et al. (2017) Amylosporusguaraniticus sp. nov. (Wrightoporiaceae, Russulales) a new neotropical species from Paraguay. Mycosphere 8(6): 1060–1070. 10.5943/mycosphere/8/6/6 [DOI] [Google Scholar]
- Caro Y, Venkatachalam M, et al. (2015) Pigments and colorants from filamentous fungi. In: Mérillon JM, Ramawat KG (Eds) Fungal Metabolites, 1st ed; Springer International Publishing: Berlin, Germany. 499–568. 10.1007/978-3-319-25001-4_26 [DOI]
- Cedeño-Sanchez M, Charria-Girón E, et al. (2023) Segregation of the genus Parahypoxylon (Hypoxylaceae, Xylariales) from Hypoxylon by a polyphasic taxonomic approach. MycoKeys 95: 131–162. 10.3897/mycokeys.95.98125 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chardin P, McCormick F. (1999) Brefeldin A: The advantage of being uncompetetive. Cell 97: 153–155. 10.1016/S0092-8674(00)80724-2 [DOI] [PubMed] [Google Scholar]
- Charria-Girón E, Surup F, Marin-Felix Y. (2022) Diversity of biologically active secondary metabolites in the ascomycete order Sordariales. Mycological Progress 21: 43. 10.1007/s11557-022-01775-3 [DOI]
- Chaverra-Muñoz L, Briem T, Hüttel S. (2022) Optimization of the production process for the anticancer lead compound illudin M: downstream processing. Microbial Cell Factories 21(1): 1–3. 10.1186/s12934-022-01886-2 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chaverra-Muñoz L, Hüttel S. (2022) Optimization of the production process for the anticancer lead compound illudin M: process development in stirred tank bioreactors. Microbial Cell Factories 21(1): 1–8. 10.1186/s12934-022-01870-w [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chen Y, Bicker W, et al. (2012) Simultaneous determination of 16 nucleosides and nucleobases by hydrophilic interaction chromatography and its application to the quality evaluation of Ganoderma. Journal of Agricultural and Food Chemistry 60: 4243–4252. 10.1021/jf300076j [DOI] [PubMed] [Google Scholar]
- Cheng T, Chepkirui C, et al. (2019) Sesquiterpenes from an Eastern African medicinal mushroom belonging to the genus Sanghuangporus. Journal of Natural Products 82(5): 1283–1291. 10.1021/acs.jnatprod.8b01086 [DOI] [PubMed] [Google Scholar]
- Cheng T, Kolařik M, et al. (2022) A re-assessment of Taxomycesandreanae, the alleged taxol-producing fungus, using comparative genomics. IMA Fungus 13: 17. 10.1186/s43008-022-00103-4 [DOI] [PMC free article] [PubMed]
- Chepkirui C, Stadler M. (2017) The genus Diaporthe: a rich source of diverse and bioactive metabolites. Mycological Progress 16(5): 477–494. 10.1007/s11557-017-1288-y [DOI] [Google Scholar]
- Chepkirui C, Yuyama KT, et al. (2018a) Microporenic Acids A-G, biofilm inhibitors, and antimicrobial agents from the basidiomycete Microporus species. Journal of Natural Products 81(4): 778–784. 10.1021/acs.jnatprod.7b00764 [DOI] [PubMed] [Google Scholar]
- Chepkirui C, Cheng T, et al. (2018b) An unprecedented spiro [furan-2, 1’-indene]-3-one derivative and other nematicidal and antimicrobial metabolites from Sanghuangporus sp. (Hymenochaetaceae, Basidiomycota) collected in Kenya. Phytochemistry Letters 25: 141–146. 10.1016/j.phytol.2018.04.022 [DOI] [Google Scholar]
- Chuankid B, Schrey H, et al. (2020) Secondary metabolites of Phlebopus species from Northern Thailand. Mycological Progress 19: 1525–1536. 10.1007/s11557-020-01643-y [DOI] [Google Scholar]
- Chuchthai MI, Pearce AA, Walker TK. (1950) The mechanism of the formation of organic acids by mould fungi; the formation of acetic and pyruvic acids in Aspergillusniger growing in glucose media. Biochemistry Journal 47(2): 135–137. 10.1042/bj0470135 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Closse A, Hauser D. (1973) Isolierung und Konstitutionsermittlung von Chrysodin. Helvetica Chimica Acta 56: 2694–2698. 10.1002/hlca.19730560803 [DOI] [PubMed] [Google Scholar]
- Čmoková A, Kolařík M, et al. (2020) Resolving the taxonomy of emerging zoonotic pathogens in the Trichophytonbenhamiae complex. Fungal Diversity 104: 333–387. 10.1007/s13225-020-00465-3 [DOI] [Google Scholar]
- Cobas C. (2020) NMR signal processing, prediction, and structure verification with machine learning techniques. Magnetic Resonanca Chemistry 58: 512–519. 10.1002/mrc.4989 [DOI] [PubMed] [Google Scholar]
- Collemare J, Seidl MF. (2019) Chromatin-dependent regulation of secondary metabolite biosynthesis in fungi: is the picture complete? FEMS Microbiology Reviews 43(6): 591–607. 10.1093/femsre/fuz018 [DOI] [PMC free article] [PubMed]
- Coluccio LM, Tilney LG. (1984) Phalloidin enhances actin assembly by preventing monomer dissociation. Journal of Cell Biology 99: 529–535. 10.1083/jcb.99.2.529 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cooper JA. (1987) Effects of cytochalasin and phalloidin on actin. Journal of Cell Biology 105: 1473–1478. 10.1083/jcb.105.4.1473 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Corrier DE. (1991) Mycotoxicosis: mechanisms of immunosuppression. Veterinary Immunology and Immunopathology 30: 73–87. 10.1016/0165-2427(91)90010-A [DOI] [PubMed] [Google Scholar]
- Cox RJ. (2007) Polyketides-proteins and genes in fungi: programmes nano-machines negin to reveal their secrets. Organic and Biomolecular Chemistry 5: 2010–2026. 10.1039/b704420h [DOI] [PubMed] [Google Scholar]
- Cox RJ. (2014) Oxidative rearrangements during fungal biosynthesis. Natural Products Reports 31: 1405–1424. 10.1039/C4NP00059E [DOI] [PubMed] [Google Scholar]
- Cox RJ. (2024) Engineered and total biosynthesis of fungal specialized metabolites. Nature Reviews Chemistry 8: 61–78. 10.1038/s41570-023-00564-0 [DOI] [PubMed] [Google Scholar]
- Critchley IA, Eckburg PB, et al. (2011) Review of ceftaroline fosamil microbiology: integrated FOCUS studies. Journal of Antimicrobial Chemotherapy 66(1): 45–51. 10.1093/jac/dkr098 [DOI] [PubMed] [Google Scholar]
- Dale JA, Dull DL, Mosher HS. (1969) α-Methoxy-α-trifluoromethylphenylacetic acid, a versatile reagent for the determination of enantiomeric composition of alcohols and amines. Journal of Organic Chemistry 34: 2543. 10.1021/jo01261a013 [DOI]
- Daum R, Kar S, Kirkpatrick P. (2007) Retapamulin. Nature Reviews Drug Discovery 6: 865–866. 10.1038/nrd2442 [DOI] [PubMed] [Google Scholar]
- Derntl C, Kluger B, et al. (2017) Transcription factor Xpp1 is a switch between primary and secondary fungal metabolism. PNAS 114: E560–E569. 10.1073/pnas.1609348114 [DOI] [PMC free article] [PubMed]
- De Silva DD, Rapior S, et al. (2013) Bioactive metabolites from macrofungi: ethnopharmacology, biological activities and chemistry. Fungal Diversity 62: 1–40. 10.1007/s13225-013-0265-2 [DOI] [Google Scholar]
- DeStefano JJ, Langlois TJ, Kirkland JJ. (2008) Characteristics of superficially-porous silica particles for fast HPLC: Some performance comparisons with sub-2-µm particles. Journal of Chromatographic Sciences 46: 254–260. 10.1093/chromsci/46.3.254 [DOI] [PubMed] [Google Scholar]
- Dewald B, Thelen M, Baggiolini (1988) Two transductions sequences are necessary for neutrophil activation by receptor agonists. Journal of Biological Chemistry 263(31): 16179–16184. 10.1016/S0021-9258(18)37575-6 [DOI] [PubMed] [Google Scholar]
- Dhanasekaran D, Shanmugapriya S, et al. (2011) Aflatoxins and aflatoxicosis in human and animals. In: Guevara-González RG (Ed.) Aflatoxins – biochemistry and molecular biology. IntechOpen. 10.5772/22717 [DOI]
- Dickinson JM, Hanson JR, et al. (1989) Structure and biosynthesis of harzianopyridone, an antifungal metabolite of Trichodermaharzianum. Journal of the Chemical Society Perkin Transactions 1, 1989: 1885–1887. 10.1039/p19890001885 [DOI]
- Ditengou FA, Müller A, et al. (2015) Volatile signalling by sesquiterpenes from ectomycorrhizal fungi reprogrammes root architecture. Nature Communications 6: 6279. 10.1038/ncomms7279 [DOI] [PMC free article] [PubMed]
- Dodds JN, Baker ES. (2019) Ion mobility spectrometry: fundamental concepts, instrumentation, applications, and the road ahead. Journal of the Americal Society for Mass Spectrometry 30(11): 2185–2195. 10.1016/j.jpba.2020.113846 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Donnelly DMX, Abe F, et al. (1985) Antibacterial sesquiterpene aryl esters from Armillariamellea. Journal of Natural Products 48(1): 1–167. 10.1021/np50037a002 [DOI] [PubMed] [Google Scholar]
- Edwards RL. (1977) Constituents of the higher fungi XVII. Methyl variegatate from the fungus Hygrophoropsisaurantiaca (Wulfen ex Fr.). Journal of Chemistry Research 11: 276.
- EFSA (2013) Scientific opinion on the risk for public and animal health related to the presence of sterigmatocystin in food and feed. EFSA Journal 11: 3254. 10.2903/j.efsa.2013.3254 [DOI]
- Ek M, Ljungquist PO, Sternström E. (1983) Indole-3-acetic acid production by mycorrhizal fungi determined by gas chromatography-mass spectrometry. New Phytologist 94: 401–407. 10.1111/j.1469-8137.1983.tb03454.x [DOI] [Google Scholar]
- Elyashberg M. (2015) Identification and structure elucidation by NMR spectroscopy, Trends in Analytical Chemistry 69: 88–97. 10.1016/j.trac.2015.02.014 [DOI]
- Elyashberg M, Argyropoulos D. (2021) Computer assisted structure elucidation (CASE): Current and future perspectives. Magnetic Resonance Chemistry 59(7): 669–690. 10.1002/mrc.5115 [DOI] [PubMed] [Google Scholar]
- Endo A. (2008) A gift from nature: the birth of the statins. Nature 14: 1050–1052. 10.1038/nm1008-1050 [DOI] [PubMed] [Google Scholar]
- Endo A, Kuroda M, Tsujita Y. (1976) ML-236A, ML-236B, and ML-236C, new inhibitors of cholesterogenesis produced by Penicilliumcitrinum. Journal of Antibiotics 29: 1346–1348. 10.7164/antibiotics.29.1346 [DOI] [PubMed] [Google Scholar]
- European Medicines Agency (2021) EU/3/21/2525: orphan designation for the treatment of invasive candiasis’. https://www.ema.europa.eu/en/medicines/human/orphan-designations/eu-3-21-252 [Accessed 21.01.2025]
- European Medicines Agency (2024) Rezzayo (rezafungin) summary of product characteristics. https://www.ema.europa.eu/en/documents/product-information/rezzayo-epar-product-information_en.pdf [Accessed 21.01.2025]
- Fasoyin OE, Wang B, et al. (2018) Carbon catabolite repression gene creA regulates morphology, aflatoxin biosynthesis and virulence in Aspergillusflavus. Fungal Genetics and Biology 115: 41–51. 10.1016/j.fgb.2018.04.008 [DOI] [PubMed] [Google Scholar]
- Faulstich H, Zobeley S, et al. (1988) Fluorescent phallotoxins as probes for filamentous actin. Journal of Muscle Research and Cell Motility 9: 370–383. 10.1007/BF01774064 [DOI] [PubMed] [Google Scholar]
- Felten J, Kohler A, et al. (2009) The ectomycorrhizal fungus Laccariabicolor stimulates lateral root formation in poplar and Arabidopsis through auxin transport and signaling. Plant Physiolology 151: 1991–2005. 10.1104/pp.109.147231 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ferrer S, Echavarren AM. (2018) Total synthesis of repraesentin F and configuration reassignment by a gold(I)-catalyzed cyclization cascade. Organic Letters 20: 5784–5788. 10.1021/acs.orglett.8b02478 [DOI] [PubMed] [Google Scholar]
- Fischer J, Schroeckh V, Brakhage AA. (2016) Awakening of fungal secondary metabolite gene clusters. In: Schmoll M, Dattenböck C. (Eds) Gene expression systems in fungi: Advancements and applications.Fungal Biology. Springer, Cham, 253–273. 10.1007/978-3-319-27951-0_11 [DOI]
- Fleming A. (1929) On the antibacterial action of cultures of a penicilium, with special reference to their use in the isolation of B.influenzae. British Journal for Experimential Pathology 10: 226–236. [Google Scholar]
- Fukaya M, Nagamine S, et al. (2023) Total biosynthesis of melleolides from Basidiomycota fungi: Mechanistic analysis of the multifunctional GMC oxidase Mld7. Angewandte Chemie, International Edition 62(44): e202308881. 10.1002/anie.202308881 [DOI] [PubMed]
- Fukushi E. (2006) Advanced NMR approaches for a detailed structure analysis of natural products. Bioscience Biotechnology Biochemistry 70: 1803–1812. 10.1271/bbb.50663 [DOI] [PubMed] [Google Scholar]
- Fuchser J, Zeeck A. (1996) Aspinolides and aspinonene/aspyrone co-metabolites, new pentaketides prodcuced by Aspergillusochraceus. Liebigs Annalen 1997: 87–95. 10.1002/jlac.199719970114 [DOI] [Google Scholar]
- Fricke J, Blei F, Hoffmeister D. (2017) Enzymatic synthesis of psilocybin. Angewandte Chemie International Edition 56(40): 12352–12355. 10.1002/anie.201705489 [DOI] [PubMed] [Google Scholar]
- Frisvad JC. (1989) The connection between the penicillia and aspergilli and mycotoxins with special emphasis on misidentified isolates. Archives of Environmental Contamnants and Toxicology 18: 452–467. 10.1007/BF01062373 [DOI] [PubMed] [Google Scholar]
- Frisvad JC. (2018) A critical review of producers of small lactone mycotoxins: Patulin, penicillic acid and moniliformin. World Mycotoxin Journal 11: 73–100. 10.3920/WMJ2017.2294 [DOI] [Google Scholar]
- Frisvad JC, Larsen TO. (2015) Chemodiversity in the genus Aspergillus. Applied Microbiolology and Biotechnolology 99: 7859–7877. 10.1007/s00253-015-6839-z [DOI] [PubMed] [Google Scholar]
- Frisvad JC, Larsen TO. (2016) Extrolites of Aspergillusfumigatus and other pathogenic species in AspergillussectionFumigati. Frontiers in Microbiology 6: 1485. 10.3389/fmicb.2015.01485 [DOI] [PMC free article] [PubMed]
- Frisvad JC, Samson RA. (2004) Emericellavenezuelensis, a new species with stellate ascospores producing sterigmatocystin and aflatoxin B1. Systematic and Applied Microbiology 27: 672–680. 10.1078/0723202042369910 [DOI] [PubMed] [Google Scholar]
- Frisvad JC, Larsen TO, et al. (2007) Secondary metabolite profiling, growth profiles and other tools for species recognition and important Aspergillus mycotoxins. Studies in Mycology 59: 31–37. 10.3114/sim.2007.59.04 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Frisvad JC, Andersen B, Thrane U. (2008) The use of secondary metabolite profiling in chemotaxonomy of filamentous fungi. Mycological Research 112: 231–240. 10.1016/j.mycres.2007.08.018 [DOI] [PubMed] [Google Scholar]
- Frisvad JC, Hubka V, et al. (2019) Taxonomy of AspergillussectionFlavi and their production of aflatoxins, ochratoxins and other mycotoxins. Studies in Mycology 93: 1–63. 10.1016/j.simyco.2018.06.001 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fuller KK, Loros JJ, Dunlap JC. (2014) Fungal photobiology: visible light as a signal for stress, space and time. Current Genetics 61: 275–288. 10.1007/s00294-014-0451-0 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gacek A, Strauss J. (2012) The chromatin code of fungal secondary metabolite gene clusters. Applied Microbial Biotechnology 95: 1389–1404. 10.1007/s00253-012-4208-8 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gärditz KF, Czesnick H. (2024) Paclitaxel–a product of fungal secondary metabolism or an artefact? Planta Medica 90: 726–735. 10.1055/a-2309-6298 [DOI] [PMC free article] [PubMed]
- Gaudêncio SP, Pereira F. (2015) Dereplication: racing to speed up the natural products discovery process. Natural Product Reports 32: 779–810. 10.1039/C4NP00134F [DOI] [PubMed] [Google Scholar]
- Gebretsadik T, Linert W, et al. (2021) LC–NMR for natural product analysis: A journey from an academic curiosity to a robust analytical tool. Science 3: 6. 10.3390/sci3010006 [DOI]
- Gheysen L, Saussez S, Journe F. (2020) Combinatorial therapies in thyroid cancer: an overview of preclinical and clinical progresses. Cells 9(4): 830. 10.3390/cells9040830 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gill M, Lally DA. (1985) A naphthalenoid pulvinic acid derivative from the fungus Pisolithustinctorius, Phytochemistry 24(6): 1351–1354. 10.1016/S0031-9422(00)81131-0 [DOI]
- Gill M, Steglich W. (1987) Pigments of fungi (Macromycetes). Progress in the Chemistry of Organic Natural Products. 51: 1–297. 10.1007/978-3-7091-6971-1 [DOI] [PubMed] [Google Scholar]
- Godtfredsen WO, Jahnsen S, et al. (1962) Fusidic acid: A new antibiotic. Nature 193: 987. 10.1038/193987a0 [DOI] [PubMed]
- Gosio B. (1893) Contributo all’etiologia della pellagra. Richerche chimiche e batteriologiche sulle alterazioni del mais. Giornale Reale Accademia Medica de Torino 61: 484–487. [Google Scholar]
- Gosio B. (1896) Richerche batteriologiche e chimiche sulle alterazioni del mais. Contributo all’etiologia della pellagra. Rivista lgiene de Sanita Publica 7: 825–849. [Google Scholar]
- Gressler M, Löhr NA, et al. (2021) Mind the mushroom: natural product biosynthetic genes and enzymes of Basidiomycota. Natural Product Reports 38(4): 702–722. 10.1039/D0NP00077A [DOI] [PubMed] [Google Scholar]
- Gritti F, Cavazzini A, et al. (2007) Comparison between the efficiencies of columns packed with fully and partitially porous C18-bonded silica materials. Journal of Chromatography A, 1157: 289–303. 10.1016/j.chroma.2007.05.030 [DOI] [PubMed] [Google Scholar]
- Gu BB, Tang J, et al. (2017) Structure, absolute configuration, and variable temperature 1H-NMR study of (–)-versiorcinols A–C, three racemates of diorcinol monoethers from the sponge-associated fungus Aspergillusversicolor 16F-11. RSC Advances 7: 50254–50263. 10.1039/C7RA06106D [DOI] [Google Scholar]
- Guo Z. (2017) The modification of natural products for medical use. Acta Pharmaceutica Sinica B 7(2): 119–136. 10.1016/j.apsb.2016.06.003 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hajjaj H, Klaébé A, et al. (2000) Medium-chain fatty acids affect citrinin production in the filamentous fungus Monascusruber. Applied and Environmental Mibrobiology 66(3): 1120–1125. 10.1128/AEM.66.3.1120-1125.2000 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Halabalaki M, Vougogiannopoulou K, et al. (2014) Recent advances and new strategies in the NMR-based identification of natural products. Current Opinions in Biotechnology 25: 1–7. 10.1016/j.copbio.2013.08.005 [DOI] [PubMed] [Google Scholar]
- Halecker S, Wennrich JP, et al. (2020) Fungal endophytes for biocontrol of ash dieback: The antagonistic potential of Hypoxylonrubiginosum. Fungal Ecology 45: 100918. 10.1016/j.funeco.2020.100918 [DOI]
- Harms K, Milic A, et al. (2021) Three new derivatives of zopfinol from Pseudorhypophilamangenotii gen. et comb. nov. Journal of Fungi 7: 181. 10.3390/jof7030181 [DOI] [PMC free article] [PubMed]
- Härri E, Loeffler W, et al. (1963) Über die Isolierung neuer Stoffwechselprodukte aus Penicilliumbrefeldianum DODGE. Helvetica Chimica Acta 46: 1235–1243. 10.1002/hlca.19630460419 [DOI] [Google Scholar]
- He Y, Cox RJ. (2016) The molecular steps of citrinin biosynthesis in fungi. Chemical Science 7: 2119–2127. 10.1039/C5SC04027B [DOI] [PMC free article] [PubMed] [Google Scholar]
- He Y, Wang B, et al. (2018) Recent advances in reconstructing microbial secondary metabolites biosynthesis in Aspergillus spp. Biotechnolgy Advances 36(3): 739–783. 10.1016/j.biotechadv.2018.02.001 [DOI] [PubMed] [Google Scholar]
- Heinig U, Scholz S, Jennewein S. (2013) Getting to the bottom of taxol biosynthesis by fungi. Fungal Diversity 60: 161–170. 10.1007/s13225-013-0228-7 [DOI] [Google Scholar]
- Helaly SE, Thongbai B, Stadler M. (2018) Diversity of biologically active secondary metabolites from endophytic and saprotrophic fungi of the ascomycete order Xylariales. Natural Product Reports 35(9): 992–1014. 10.1039/C8NP00010G [DOI] [PubMed] [Google Scholar]
- Heussner A, Bingle L, et al. (2015) Comparative ochratoxin toxicity: a review of the available data. Toxins 7: 4253–4282. 10.3390/toxins7104253 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Himstedt R, Wagner S, et al. (2020) Formaldehyde as a chemical defence agent of fruiting bodies of Mycenarosea against the mycoparasite Spinellusfusiger and its role in the generation of the red pyrroloquinoline alkaloid mycenarubin C. ChemBioChem 21: 1613–1620. 10.1002/cbic.201900733 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hofmann A, Heim R, et al. (1958) Psilocybin, a psychotropic substance from the Mexican mushroom Psilocybemexicana Heim. Experientia 14: 107–109. 10.1007/BF02159243 [DOI] [PubMed] [Google Scholar]
- Höfs R, Walker M, Zeeck A. (2000) Hexacyclinic acid, a polyketide from Streptomyces with a novel carbon skeleton. Angewandte Chemie International Edition 39(18): 3258–3261. [DOI] [PubMed] [Google Scholar]
- Hönig M, Carreira EM. (2020) Total synthesis and structural revision of a harziane diterpenoid. Angewandte Chemie International Edition 59: 1192–1196. 10.1002/anie.201912982 [DOI] [PubMed] [Google Scholar]
- Houbraken J, de Vries RP, Samson RA. (2014) Modern taxonomy of biotechnologically important Aspergillus and Penicillium species. Advances in Applied Microbiology 86: 199–249. 10.1016/B978-0-12-800262-9.00004-4 [DOI] [PubMed] [Google Scholar]
- Houbraken J, Kocsubé S, et al. (2020) Classification of Aspergillus, Penicillium, Talaromyces and related genera (Eurotiales): an overview of families, genera, subgenera, sections, series and species. Studies in Mycology 95: 5–169. 10.1016/j.simyco.2020.05.002 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hüttel W. (2021) Echinocandins: structural diversity, biosynthesis, and development of antimycotics. Applied Microbiology and Biotechnology 105: 55–66. 10.1007/s00253-020-11022-y [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hutchings MI, Truman AW, Wilkinson B. (2019) Antibiotics: past, present and future. Current Opinions in Microbiology 9(51): 72–80. 10.1016/j.mib.2019.10.008 [DOI] [PubMed] [Google Scholar]
- Hyde KD, Norphanphoun C, et al. (2018) Thailand’s amazing diversity: up to 96% of fungi in northern Thailand may be novel. Fungal. Diversity 93: 215–239. 10.1007/s13225-018-0415-7 [DOI] [Google Scholar]
- Hyde KD, Xu JC, et al. (2019) The amazing potential of fungi, 50 ways we can exploit fungi industrially. Fungal Diversity 97: 1–136. 10.1007/s13225-019-00430-9 [DOI] [Google Scholar]
- Hyde KD, Baldrian P, et al. (2024) Current trends, limitations and future research in the fungi? Fungal Diversity 125: 1–71. 10.1007/s13225-023-00532-5 [DOI]
- Ito T, Odake T, et al. (2011) High-throughput profiling of microbial extracts. Journal of Natural Products 74(5): 983–988. 10.1021/np100859a [DOI] [PubMed] [Google Scholar]
- Iwamoto T, Fujie A, et al. (1994) WF11899A, B and C, novel antifungal lipopeptides. Journal of Antibiotics 47: 1084–1091. 10.7164/antibiotics.47.1084 [DOI] [PubMed] [Google Scholar]
- Jackson CL. (2018) Activators and effectors of the small G protein Arf1 in regulation of Golgi dynamics during the cell division cycle. Frontiers in Cell and Developmental Biology 6: 29. 10.3389/fcell.2018.00029 [DOI] [PMC free article] [PubMed]
- Jahn L, Schafhauser T, et al. (2017) Linking secondary metabolites to biosynthesis genes in the fungal endophyte Cyanodermellaasteris: The anti-cancer bisanthraquinone skyrin. Journal of Biotechnology 257: 233–239. 10.1016/j.jbiotec.2017.06.410 [DOI] [PubMed] [Google Scholar]
- Jayanetti DR, Yue Q, et al. (2015) Hypocoprins A–C: new sesquiterpenoids from the coprophilous fungus Hypocoprarostrata. Journal of Natural Products 78(3): 396–401. 10.1021/np5007718 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jayanetti DR, Li Y, et al. (2017) Benzophenone and fimetarone derivatives from the coprophilous fungus Delitschiaconfertaspora. Journal of Natural Products 80(3): 707–712. 10.1021/acs.jnatprod.6b01091 [DOI] [PubMed] [Google Scholar]
- Jiménez-Romero C, Ortiz I, et al. (2010) Bioactive cycloperoxides isolated from the Puerto Rican sponge Plakortishalichondrioides. Journal of Natural Products 73: 1694–1700. 10.1021/np100461t [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kaewnarin K, Limjiasahapong S, et al. (2021) High-Resolution QTOF-MRM for highly accurate identification and quantification of trace levels of triterpenoids in mycelium. Journal of the American Society for Mass Spectrometry 32: 2451–2462. 10.1021/jasms.1c00175 [DOI] [PubMed] [Google Scholar]
- Kahlert L, Schotte C, Cox RJ. (2021) Total mycosynthesis: rational bioconstruction and bioengineering of fungal natural products. Synthesis 53(14): 2381–2394. 10.1055/a-1401-2716 [DOI] [Google Scholar]
- Kapoor K, Finer-Moore JS, et al. (2016) Mechanism of inhibition of human glucose transporter GLUT1 is conserved between cytochalasin B and phenylalanine amides. PNAS 113(17): 4711–4716. 10.1073/pnas.1603735113 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kargbo RB. (2020) Psilocybin therapeutic research: the present and future paradigm. ACS Medicinal Chemistry Letters 11: 399–402. 10.1021/acsmedchemlett.0c00048 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Karve S, Werner ME, et al. (2012) Revival of the abandoned therapeutic wortmannin by nanoparticle drug delivery. PNAS 109(21): 8230–8235. 10.1073/pnas.1120508109 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Karwehl S, Stadler M. (2017) Exploitation of fungal biodiversity for discovery of novel antibiotics. Current Topics in Microbiology and Immunology 398: 303–338. 10.1007/82_2016_496 [DOI] [PubMed] [Google Scholar]
- Katz L, Baltz RH. (2016) Natural product discovery: past, present, and future. Journal of Industrial and Microbial Biotechnology 43: 155–167. 10.1007/s10295-015-1723-5 [DOI] [PubMed] [Google Scholar]
- Kavanagh F, Hervey A, Robbins WJ. (1951) Antibiotic substances from Basidiomycetes: VIII. Pleurotusmutilus (Fr.) Sacc. and Pleurotuspasseckerianus Pilat. PNAS 37: 570–574. 10.1073/pnas.37.9.570 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Keller NP. (2015) Translating biosynthetic gene clusters into fungal armor and weaponry. Nature Chemical Biology 11: 671–677. 10.1038/nchembio.1897 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Keller NP. (2019) Fungal secondary metabolism: regulation, function and drug discovery. Nature Reviews Microbiology 17(3): 167–180. 10.1038/s41579-018-0121-1 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kim L, Marriott PJ. (2021) Preparative gas chromatography. In: Poole CF. (Ed.) Handbooks in Separation Science, Gas Chromatography (2nd Ed.), Elsevier, 487–504. 10.1016/B978-0-12-820675-1.00039-3 [DOI]
- Kindler BLJ, Spiteller P. (2007) Chemical defense of the crust fungus Aleurodiscusamorphus by a tailor-made cyanogenic cyanohydrin ether. Angewandte Chemie International Edition 46: 8076–8078. 10.1002/anie.200702481 [DOI] [PubMed] [Google Scholar]
- Kjærbølling I, Mortensen UH, et al. (2019) Strategies to establish the link between biosynthetic gene clusters and secondary metabolites. Fungal Genetics and Biology 130: 107–121. 10.1016/j.fgb.2019.06.001 [DOI] [PubMed] [Google Scholar]
- Klausner RD, Donaldson JG, Lippincott-Schwartz J. (1992) Brefeldin A: Insights into the control of membrane traffic and organelle structure. Journal of Cell Biology 116(5): 1071–1080. 10.1083/jcb.116.5.1071 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kluepfel D, Bagli J, et al. (1972) Myriocin, a new antifungal antibiotic from Myriococcumalbomyces. Journal of Antibiotics 25: 109–115. 10.7164/antibiotics.25.109 [DOI] [PubMed] [Google Scholar]
- Kobayashi Y, Lee J, et al. (1999) Toward creation of a universal NMR database for the stereochemical assignment of acyclic compounds: The case of two contiguous propionate units. Organic Letters 1: 2177–2180. 10.1021/ol9903786 [DOI] [PubMed] [Google Scholar]
- Kobayashi Y, Tan CH, Kishi Y. (2000a) Toward creation of a universal NMR database for stereochemical assignment: The case of 1,3,5-trisubstituted acyclic systems. Helvetica Chimica Acta 83: 2562–2571. [DOI] [Google Scholar]
- Kobayashi Y, Tan CH, Kishi Y. (2000b) Stereochemical assignment of the C21–C38 portion of the desertomycin/oasomycin class of natural products by using universal NMR databases: prediction. Angewandte Chemie Internatinal Edition 39: 4279–4281. [DOI] [PubMed] [Google Scholar]
- Kobayashi Y, Tan CH, Kishi Y. (2001) Toward creation of a universal NMR database for stereochemical assignment: Complete structure of the desertomycin/oasomycin class of natural products. Journal of the Americal Chemical Society 123: 2076–2078. 10.1021/ja004154q [DOI] [PubMed] [Google Scholar]
- Kocsubé S, Perrone G, et al. (2016) Aspergillus is monophyletic: evidence from multiple gene phylogenies and extrolites profiles. Studies in Mycology 85: 199–213. 10.1016/j.simyco.2016.11.006 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Koizumi T, Yoshiike F, et al. (2004) Phase I trial of bi-weekly paclitaxel and gemcitabine as second-line therapy for patients with non-scmall-cell lung cancer previously treated with platinum-based chemotherapy. Medical Oncology 21(2): 133–137. 10.1385/MO:21:2:133 [DOI] [PubMed] [Google Scholar]
- Krappmann S. (2014) Genetic surgery in fungi: Employing site-specific recombinases for genome manipulation. Applied Microbiology and Biotechnology 98(5): 1971–1982. 10.1007/s00253-013-5480-y [DOI] [PubMed] [Google Scholar]
- Kretz R, Wendt L, et al. (2017) The effect of cytochalasans on the actin cytoskeleton of eukaryotic cells and preliminary structure-activity relationships. Biomolecules 9(2): 73. 10.3390/biom9020073 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kuephadungphan W, Macabeo APG, et al. (2021) Discovery of novel biologically active secondary metabolites from Thai mycodiversity with anti-infective potential. Current Research in Biotechnology 3: 160–172. 10.1016/j.crbiot.2021.05.003 [DOI] [Google Scholar]
- Kuhnert E, Collemare J. (2022) A genomic journey in the secondary metabolite diversity of fungal plant and insect pathogens: from functional to population genomics. Current Opinions in Microbiology 69: 102178. 10.1016/j.mib.2022.102178 [DOI] [PubMed]
- Kuhnert E, Fournier J, et al. (2014) New Hypoxylon species from Martinique and new evidence on the molecular phylogeny of Hypoxylon based on ITS rDNA and β-tubulin data. Fungal Diversity 64: 181–203. 10.1007/s13225-013-0264-3 [DOI] [Google Scholar]
- Kuhnert E, Sir EB, et al. (2017) Phylogenetic and chemotaxonomic resolution of the genus Annulohypoxylon (Xylariaceae) including four new species. Fungal Diversity 85: 1–43. 10.1007/s13225-016-0377-6 [DOI] [Google Scholar]
- Kuhnert E, Munoz JCN, et al. (2021) Secondary metabolite biosynthetic diversity in the fungal family Hypoxylaceae and Xylariahypoxylon. Studies in Mycology 99: 100118. 10.1016/j.simyco.2021.100118 [DOI] [PMC free article] [PubMed]
- Kwan EE, Huang SG. (2008) Structural elucidation with NMR spectroscopy: practical strategies for organic chemists. European Journal of Organic Chemistry 16: 2671–2688. 10.1002/ejoc.200700966 [DOI] [Google Scholar]
- Lambert C, Pourmoghaddam MJ, et al. (2021) Resolution of the Hypoxylonfuscum complex (Hypoxylaceae, Xylariales) and discovery and biological characterisation of two of its prominent secondary metabolites. Journal of Fungi 7(2): 131. 10.3390/jof7020131 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lambert C, Schmidt K, et al. (2023) Cytochalasans and their impact on actin filament remodeling. Biomolecules 13(8): 1247. 10.3390/biom13081247 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lan D, Wu B. (2020) Chemistry and bioactivities of secondary metabolites from the genus Talaromyces. Chemistry and Biodiversity 17(8): e2000229. 10.1002/cbdv.202000229 [DOI] [PubMed]
- Latif Z, Sarker SD. (2012) Isolation of natural products by preparative high performance liquid chromatography (Prep-HPLC). Methods in Molecular Biolology 864: 255–274. 10.1007/978-1-61779-624-1_10 [DOI] [PubMed] [Google Scholar]
- Lawrinowitz S, Wurlitzer JM, et al. (2022) Blue light-dependent pre-mRNA splicing controls pigment biosynthesis in the mushroom Teranacaerulea. Microbiol Spectr 10: e01065-22. 10.1128/spectrum.01065-22 [DOI] [PMC free article] [PubMed]
- Lazarus C, Williams K, Bailey AM. (2014) Reconstructing fungal natural product biosynthetic pathways. Natural Product Reports 31(10): 1339–1347. 10.1039/C4NP00084F [DOI] [PubMed] [Google Scholar]
- Lee J, Kobayashi Y, et al. (1999) Toward creation of a universal NMR database for the stereochemical assignment of acyclic compounds: Proof of concept. Organic Letters 1(13): 2181–2184. 10.1021/ol990379y [DOI] [PubMed] [Google Scholar]
- Lee MR, Dukan E, Milne I. (2018) Amanitamuscaria (fly agaric): from a shamanistic hallucinogen to the search for acetylcholine. Journal of the Royal College of Physicians of Edinburgh 48: 85–91. 10.4997/jrcpe.2018.119 [DOI] [PubMed] [Google Scholar]
- Lenore E, Asbel MD, et al. (2000) Cephalosporins, carbapenems, and monobactams. Infectious Disease Clinics of North America 14: 435–447. 10.1016/S0891-5520(05)70256-7 [DOI] [PubMed] [Google Scholar]
- Lenz C, Sherwood A, et al. (2020) Taking different roads: l-tryptophan as the origin of Psilocybe natural products. ChemPlusChem 85: 1–9. 10.1002/cplu.202000581 [DOI] [PubMed] [Google Scholar]
- Li XC, Ferreira D, Ding Y. (2010) Determination of absolute configuration of natural products: Theoretical calculation of electronic circular dichroism as a tool. Current Organic Chemistry 14: 1678–1697. 10.2174/138527210792927717 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Li YP, Pan YF, et al. (2013) Lower citrinin production by gene disruption of ctnB Involved in citrinin biosynthesis in Monascusaurantiacus Li AS3.4384. Journal of Agricultural and Food Chemistry 61(30): 7397–7402. 10.1021/jf400879s [DOI] [PubMed] [Google Scholar]
- Li G, Jian T, et al. (2022) Application of metabolomics in fungal research. Molecules 27(21): 7365. 10.3390/molecules27217365 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Linington RG, Williams PG, MacMillan JB. (2015) Problems in organic structure deteremination: A practical approach to NMR spectroscopy. CRC Press, Boca Raton, Fl. 10.1201/b19329 [DOI]
- Lippincott-Schwartz J, Yuan LC, et al. (1989) Rapid redistribution of Golgi proteins into the ER in cells treated with brefeldin A: Evidence for membrane cycling from Golgi to ER. Cell 56: 801–813. 10.1016/0092-8674(89)90685-5 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Liu Y, Shreder KR, et al. (2005) Wortmannin, a widely used phosphoinositide 3-kinase inhibitor, also potently inhibits mammalian Polo-like kinase. Chemical Biology 12: 99–107. 10.1016/j.chembiol.2004.11.009 [DOI] [PubMed] [Google Scholar]
- Liu YF, Zhang YH, et al. (2020a) Microketides A and B, polyketides from a gorgonian-derived Microsphaeropsis sp. fungus. Journal of Natural Products 83: 1300–1304. 10.1021/acs.jnatprod.0c00144 [DOI] [PubMed] [Google Scholar]
- Liu F, Hu W, et al. (2020b) AUTOPHAGY-RELATED14 and its associated phosphatidylinositol 3-kinase complex promote autophagy in Arabidopsis. Plant Cell 32: 3939–3960. 10.1105/tpc.20.00285 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lohmann JS, von Nussbaum M, et al. (2018) Rosellin A and B, two red diketopiperazine alkaloids from the mushroom Mycenarosella. Tetrahedron 74(38): 5113–5118. 10.1016/j.tet.2018.06.049 [DOI] [Google Scholar]
- Luo Z, Ren H, et al. (2017) The PacC transcription factor regulates secondary metabolite production and stress response, but has only minor effects on virulence in the insect pathogenic fungus Beauveriabassiana. Environmental Mibrobiology 19(2): 788–802. 10.1111/1462-2920.13648 [DOI] [PubMed] [Google Scholar]
- Lynen F, Wieland U. (1938) Über die Giftstoffe des Knollenblätterpilzes. Liebigs Annalen 533: 521–522. 10.1002/jlac.19385330105 [DOI] [Google Scholar]
- Lysøe E, Pasquali M, et al. (2011) The transcription factor FgStuAp influences spore development, pathogenicity, and secondary metabolism in Fusariumgraminearum. Molecular Plant-Microbe Interactions 24(1): 54–67. 10.1094/MPMI-03-10-0075 [DOI] [PubMed] [Google Scholar]
- Ma X, Liang X, et al. (2020) New alkaloids and isocoumarins from the marine gorgonian-derived fungus Aspergillus sp. SCSIO 41501. Natural Product Research 34(14): 1992–2000. 10.1080/14786419.2019.1569660 [DOI] [PubMed] [Google Scholar]
- Macheleidt J, Mattern DJ, et al. (2016) Regulation and role of fungal secondary metabolites. Annual Review of Genetics 50(1): 371–392. 10.1146/annurev-genet-120215-035203 [DOI] [PubMed] [Google Scholar]
- Madhosingh C. (1966) Pigmented bacteriostatic substances abd amino acids produced by Phlebopussulphureus and Phlebopuslignicola. Applied Microbiology 14(3): 331–336. 10.1128/am.14.3.331-336.1966 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Makrerougras M, Coffinier R, et al. (2017) Total synthesis and structural revision of chaetoviridins A. Organic Letters 19(15): 4146–4149. 10.1021/acs.orglett.7b02053 [DOI] [PubMed] [Google Scholar]
- Mangoni A. (2012) Strategies for structural assignment of marine natural products through advanced NMR-based techniques. In: Handbook of Marine Natural Products; Springer: Dordrecht, The Netherlands, 518–546. 10.1007/978-90-481-3834-0_8 [DOI]
- Mapook A, Hyde KD, et al. (2022) Ten decadal advances in fungal biology leading towards human well-being. Fungal Diversity 116: 547–614. 10.1007/s13225-022-00510-3 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Marfey P. (1984) Determination of D-amino acids. II. Use of a bifunctional reagent, 1,5-difluoro-2,4-dinitrobenzene. Carlsberg Research Communications 49: 591. 10.1007/BF02908688 [DOI]
- Markina NM, Kotlobay AA, Tsarkova AS. (2020) Heterologous metabolic pathways: Strategies for optimal expression in eukaryotic hosts. Acta Naturae 12(2): 28–39. 10.32607/actanaturae.10966 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Marik T, Tyagi C, et al. (2019) Structural diversity and bioactivities of peptaibol compounds from the longibrachiatum clade of the filamentous fungal genus Trichoderma. Frontiers in Microbiology 10: 1434. 10.3389/fmicb.2019.01434 [DOI] [PMC free article] [PubMed]
- Marlot L, Faure K. (2017) Preparative two dimensional separations involving liquid–liquid chromatography. Journal of Chromatography A 1494: 1–17. 10.1016/j.chroma.2017.03.031 [DOI] [PubMed] [Google Scholar]
- Martin GE, Buevich AV, et al. (2013) Coniothyrione: anatomy of a structure revision. Magnetic Resonance Chemistry 51(7): 383–389. 10.1002/mrc.3952 [DOI] [PubMed] [Google Scholar]
- Martin GE, Williams AJ, Rovnyak D. (2015) New directions in natural products NMR: What can we learn by examining how the discipline has evolved? In: Williams AJ, Martin GE, Rovnyak D. (Eds) Modern NMR Approaches to the Structure Elucidation of Natural Products, Vol.1 Instrumentation and Software. Royal Society of Chemistry: Cambridge, U.K., 1–25. 10.1039/9781849735186-00001 [DOI]
- Masike K, Stander MA, de Villiers A. (2021) Recent applications of ion mobility spectrometry in natural product research. Journal of Pharmaceutical and Biomedical Analytics 195: 113846. 10.1016/j.jpba.2020.113846 [DOI] [PubMed]
- Matio Kemkuignou B, Moussa AY, et al. (2022) Terpenoids and meroterpenoids from cultures of two grass-associated species of Amylosporus (Basidiomycota). Journal of Natural Products 85(4): 846–856. 10.1021/acs.jnatprod.1c00975 [DOI] [PubMed] [Google Scholar]
- Matsuda Y, Abe I. (2016) Biosynthesis of fungal meroterpenoids. Natural Product Reports 33: 26–53. 10.1039/C5NP00090D [DOI] [PubMed] [Google Scholar]
- Matsuda Y, Mitsuhashi T, et al. (2016) Astellifadiene: Structure determination by NMR spectroscopy and crystalline sponge method, and elucidation of its biosynthesis. Angewandte Chemie International Edition 55(19): 5785–5788. 10.1002/anie.201601448 [DOI] [PubMed] [Google Scholar]
- Matsumori N, Murata M. (2017) NMR studies on natural product—Stereochemical determination and conformational analysis in solution and in membrane. In: The Nuclear Magnetic Resonance Society of Japan Experimental Approaches of NMR Spectroscopy. Springer, Singapore, 383–414. 10.1007/978-981-10-5966-7_14 [DOI]
- Matsumori N, Kaneno D, et al. (1999) Stereochemical determination of acyclic structures based on carbon-proton spin-coupling constants. A method of configuration analysis for natural products. Journal of Organic Chemistry 64(3): 866–876. 10.1021/jo981810k [DOI] [PubMed] [Google Scholar]
- Mazloom-Farsibaf H, Farzam F, et al. (2021) Comparing lifeact and phalloidin for super-resolution imaging of actin in fixed cells. PLOS ONE 16(1): e0246138. 10.1371/journal.pone.0246138 [DOI] [PMC free article] [PubMed]
- McDonald S, Abbott JM, Higgins SP. (2004) Prophylactic ergometrine-oxytocin versus oxytocin for the third stage of labour. Cochrane Database Systematic Reviews 2004(1): CD000201. 10.1002/14651858.CD000201.pub2 [DOI] [PMC free article] [PubMed]
- Mechlinski W, Schaffner CP, et al. (1970) Structure and absolute configuration of the polyene macrolide antibiotic amphotericin mechliB. Tetrahedron Letters 11(44): 3873–3876. 10.1016/S0040-4039(01)98612-5 [DOI] [Google Scholar]
- Medema M, Kottmann R, et al. (2015) Minimum information about a biosynthetic gene cluster. Nature Chemical Biology 11: 625–631. 10.1038/nchembio.1890 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Midland SL, Izac RR, et al. (1982) Melleolide, a new antibiotic from Armillariamellea. Tetrahedron Letters 23(25): 2515–2518. 10.1016/S0040-4039(00)87383-9 [DOI] [Google Scholar]
- Miethke M, Pieroni M, et al. (2021) Towards the sustainable discovery and development of new antibiotics. Nat Rev Chem.19: 1–24. 10.1038/s41570-021-00313-1 [DOI] [PMC free article] [PubMed]
- Misumi Y, Misumi Y, et al. (1986) Novel blockade by brefeldin A of intracellular transport of secretory proteins in cultured rat hepatocytes. Journal of Biological Chemisty 261(24): 11398–11403. 10.1016/S0021-9258(18)67398-3 [DOI] [PubMed] [Google Scholar]
- Mitsuhashi T, Barra L, et al. (2020) Exploiting the potential of meroterpenoid cyclases to expand the chemical space of fungal meroterpenoids. Angewandte Chemie International Edition 59: 23772–23781. 10.1002/ange.202011171 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mizuno K, Tsujino M, et al. (1974) Studies on bredinin: Isolation, characterization and biological properties. Journal of Antibiotics 27(10): 775–782. 10.7164/antibiotics.27.775 [DOI] [PubMed] [Google Scholar]
- Motiram-Corral K, Nolis P, et al. (2020) LR-HSQMBC versus LR-selHSQMBC: Enhancing the observation of tiny long-range heteronuclear NMR correlations. Journal of Natural Products 83: 1275–1282. 10.1021/acs.jnatprod.0c00058 [DOI] [PubMed] [Google Scholar]
- Moussa AY, Lambert C, et al. (2020) New peptaibiotics and a cyclodepsipeptide from Ijuhyavitellina: Isolation, identification, cytotoxic and nematicidal activities. Antibiotics 9(3): 132. 10.3390/antibiotics9030132 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mudalungu CM, Richter C, et al. (2016) Laxitextines A and B, cyathane xylosides from the tropical fungus Laxitextumincrustatum. Journal of Natural Products 79(4): 894–898. 10.1021/acs.jnatprod.5b00950 [DOI] [PubMed] [Google Scholar]
- Muria-Gonzalez MJ, Chooi YH, et al. (2015) The past, present and future of secondary metabolite research in the Dothideomycetes. Molecular Plant Pathology 16(1): 92–107. 10.1111/mpp.12162 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nair MG. (1998) Fumonisins and human health. Annals of Tropical Paediatry 18: 47–52. 10.1080/02724936.1998.11747980 [DOI] [PubMed] [Google Scholar]
- Nazir M, Saleem M, et al. (2021) Meroterpenoids: A comprehensive update insight on structural diversity and biology. Biomolecules 11: 957. 10.3390/biom11070957 [DOI] [PMC free article] [PubMed]
- Nebenführ A, Ritzenthaler C, Robinson DG. (2002) Brefeldin A: Deciphering an enigmatic Inhibitor of secretion. Plant Physiology 130: 1102–1108. 10.1104/pp.011569 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Newman DJ, Cragg GM. (2020) Natural products as sources of new drugs over the nearly four decades from 01/1981 to 09/2019. Journal of Natural Products 83: 770–803. 10.1021/acs.jnatprod.9b01285 [DOI] [PubMed] [Google Scholar]
- Newton GGF, Abraham EP. (1955) Cephalosporin C, a new antibiotic containing sulphur and D-α-aminoadipic acid. Nature 175(4456): 548. 10.1038/175548a0 [DOI] [PubMed] [Google Scholar]
- Niego AGT, Lambert C, et al. (2023) The contribution of fungi to the global economy. Fungal Divers 121: 95–137. 10.1007/s13225-023-00520-9 [DOI] [Google Scholar]
- Nielsen KF, Larsen TO. (2015) The importance of mass spectrometric dereplication in fungal secondary metabolite analaysis. Frontiers in Microbiology 6: 71. 10.3389/fmicb.2015.00071 [DOI] [PMC free article] [PubMed]
- Nielsen KF, Mogensen JM, et al. (2009) Review of secondary metabolites and mycotoxins from the Aspergillusniger group. Analytical and Bioanalytical Chemistry 395: 1225–1242. 10.1007/s00216-009-3081-5 [DOI] [PubMed] [Google Scholar]
- Nielsen KF, Mansson M, et al. (2011) Dereplication of microbial natural products by LC-DAD-TOFMS. Journal of Natural Products 74: 2338–2348. 10.1021/np200254t [DOI] [PubMed] [Google Scholar]
- Niu TK, Pfeifer AC, et al. (2005) Dynamics of GBF1, a brefeldin A-sensitive Arf1 exchange factor at the Golgi. Molecular Biology of the Cell 16: 1213–1222. 10.1091/mbc.e04-07-0599 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Novak R. (2011) Are pleuromutilin antibiotics finally fit for human use? Annuals of the New York Academic Science 1241: 71–81. 10.1111/j.1749-6632.2011.06219.x [DOI] [PubMed]
- Nukina M. (1987) Pyrichalasin H, a new phytotoxic metabolite belonging to the cytochalasans from Pyriculariagrisea (Cooke) Saccardo. Agricultural and Biological Chemistry 51(9): 2625–2628. 10.1080/00021369.1987.10868388 [DOI] [Google Scholar]
- Ondeyka JG, Zink D, et al. (2007) Coniothyrione, a chlorocyclopentandienylbenzopyrone as a bacterial protein synthesis inhibitor discovered by antisense technology. Journal of Natural Products 70: 668. 10.1021/np060557d [DOI] [PubMed]
- Ortega HE, Torres-Mendoza D, et al. (2021) Structurally uncommon secondary metabolites derived from endophytic fungi. Journal of Fungi 7(7): 570. 10.3390/jof7070570 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Oxford AE, Raistrick H, Simonart P. (1939) Studies in the biochemistry of micro-organisms: Griseofulvin, C17H17O6Cl, a metabolic product of Penicilliumgriseo-fulvum Dierckx. Biochemical Journal 33: 240–248. 10.1042/bj0330240 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Palermo A. (2023) Metabolomics- and systems-biology-guided discovery of metabolite lead compounds and druggable targets (2023) Drug Discovery Today 28(2): 103460. 10.1016/j.drudis.2022.103460 [DOI] [PubMed]
- Pedras MSC, Yu Y, et al. (2005) Metabolites produced by the phytopathogenic fungus Rhizoctoniasolani: Isolation, chemical structure determination, syntheses and bioactivity. Zeitschrift für Naturforschung 60C(9–10): 717–722. 10.1515/znc-2005-9-1010 [DOI] [PubMed]
- Peláez F, Cabello A, et al. (2000) The discovery of enfumafungin, a novel antifungal compound produced by an endophytic Hormonema species biological activity and taxonomy of the producing organisms. Systematic and Applied Microbiolology 23(3): 333–343. 10.1016/S0723-2020(00)80062-4 [DOI] [PubMed] [Google Scholar]
- Pelham HRB. (1991) Multiple targets for brefeldin A. Cell 67: 449–451. 10.1016/0092-8674(91)90517-3 [DOI] [PubMed] [Google Scholar]
- Perrin RM, Federova ND, et al. (2007) Transcriptional regulation of chemical diversity in Aspergillusfumigatus by LaeA. PLOS Pathogens 3(4): e50. 10.1371/journal.ppat.0030050 [DOI] [PMC free article] [PubMed]
- Peters S, Spiteller P. (2007) Sanguinones A and B, blue pyrroloquinoline alkaloids from the fruiting bodies of the mushroom Mycenasanguinolenta. Journal of Natural Products 70(8): 1274–1277. 10.1021/np070179s [DOI] [PubMed] [Google Scholar]
- Petersen AB, Rønnest MH, et al. (2014) The chemistry of griseofulvin. Chemical Reviews 114: 12088–12107. 10.1021/cr400368e [DOI] [PubMed] [Google Scholar]
- Peterson JR, Mitchison TJ. (2002) Small molecules, big impact: A history of chemical inhibitors and the cytoskeleton. Chemical Biology 9: 1275–1285. 10.1016/S1074-5521(02)00284-3 [DOI] [PubMed] [Google Scholar]
- Pfütze S, Khamsim A, et al. (2023a) Heimionones A–E, new sesquiterpenoids produced by Heimiomyces sp., a basidiomycete collected in Africa. Molecules 28(9): 3723. 10.3390/molecules28093723 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pfütze S, Khamsim A, et al. (2023b) Calamene-type sesqui-, mero-, and bis-sesquiterpenoids from cultures of Heimiomyces sp., a basidiomycete collected in Africa. Journal of Natural Products 86(2): 390–397. 10.1021/acs.jnatprod.2c01015 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pfütze S, Charria‐Girón E, et al. (2024) Depicting the chemical diversity of bioactive meroterpenoids produced by the largest organism on Earth. Angewandte Chemie International Edition 63(16): e202318505. 10.1002/anie.202318505 [DOI] [PubMed]
- Pourmoghaddam MJ, Lambert C, et al. (2020) Discovery of a new species of the Hypoxylonrubiginosum complex from Iran and antagonistic activities of Hypoxylon spp. against the Ash Dieback pathogen, Hymenoscyphusfraxineus, in dual culture. MycoKeys 66: 105–133. 10.3897/mycokeys.66.50946 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Porras-Alfaro A, Bayman P. (2011) Hidden fungi, emergent properties: endophytes and microbiomes. Annual Reviews in Phytopathology 49: 291–315. 10.1146/annurev-phyto-080508-081831 [DOI] [PubMed] [Google Scholar]
- Powis G, Bonjouklian R, et al. (1994) Wortmannin, a potent and selective inhibitor of phosphatidylinositol-3-kinase. Cancer Research 54: 2419–2423. https://cancerres.aacrjournals.org/content/canres/54/9/2419.full.pdf [PubMed] [Google Scholar]
- Proctor RH, McCormick SP, et al. (2018) Evolution of structural diversity of trichothecenes, a family of toxins produced by plant pathogenic and entomopathogenic fungi. PLOS Pathogens 14(4): e1006946. 10.1371/journal.ppat.1006946 [DOI] [PMC free article] [PubMed]
- Pucci V, Di Palma S, et al. (2009) A novel strategy for reducing phospholipids-based matrix effect in LC-ESI-MS bioanalysis by means of HybridSPE. Journal of Pharmaceutical and Biomedical Analysis 50: 867–871. 10.1016/j.jpba.2009.05.037 [DOI] [PubMed] [Google Scholar]
- Ráduly Z, Szabó L, et al. (2020) Toxicolocial and medical aspects of Aspergillus-derived mycotoxins entering the feed and food chain. Frontiers in Microbiology 10: 2908. 10.3389/fmicb.2019.02908 [DOI] [PMC free article] [PubMed]
- Raimi A, Adeleke R. (2021) Bioprospecting of endophytic microorganisms for bioactive compounds of therapeutic importance. Archives of Microbiology 203: 1917–1942. 10.1007/s00203-021-02256-z [DOI] [PubMed] [Google Scholar]
- Raja HA, Miller AN, et al. (2017) Fungal identification using molecular tools: a primer for the natural products research community. Journal of Natural Products 80(3): 756–770. 10.1021/acs.jnatprod.6b01085 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rank C, Nielsen KF, et al. (2011) Distribution of sterigmatocystin in filamentous fungi. Fungal Biology 115(4–5): 406–420. 10.1016/j.funbio.2011.02.013 [DOI] [PubMed] [Google Scholar]
- Reynolds WF, Mazzola EP. (2015) Nuclear magnetic resonance in the structural elucidation of natural products. In: Kinghorn A, Falk H, Kobayashi J (Eds) Progress in the Chemistry of Organic Natural Products, vol. 100. Springer, Cham. 10.1007/978-3-319-05275-5_3 [DOI] [PubMed]
- Richardson MJ. (2001) Diversity and occurrence of coprophilous fungi. Mycological Research 105(4): 387–402. 10.1017/S0953756201003884 [DOI] [Google Scholar]
- Rinkel J, Dickschat JS. (2015) Recent highlights in biosynthesis research using stable isotopes. Beilstein Journal of Organic Chemistry 11: 2493–2508. 10.3762/bjoc.11.271 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rivera-Illanes D, Recabarren-Gajardo G. (2024) Classics in Chemical Neuroscience: Muscimol. ACS Chemical Neuroscience 15(18): 3257–3269. 10.1021/acschemneuro.4c00304 [DOI] [PubMed] [Google Scholar]
- Rokas A, Wisecaver JH, Lind AL. (2018) The birth, evolution and death of metabolic gene clusters in fungi. Nature Reviews Microbiology 16: 731–744. 10.1038/s41579-018-0075-3 [DOI] [PubMed] [Google Scholar]
- Rokas A, Mead ME, et al. (2020) Biosynthetic gene clusters and the evolution of fungal chemodiversity. Natural Products Reports 37(7): 868–878. 10.1039/C9NP00045C [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rohlfs M, Churchill ACL. (2011) Fungal secondary metabolites as modulators of interactions with insects and other arthropods. Fungal Genetetics and Biology 48(1): 23–34. 10.1016/j.fgb.2010.08.008 [DOI] [PubMed] [Google Scholar]
- Roze LV, Chanda A, et al. (2011) Stress-related transcription factor AtfB integrates secondary metabolism with oxicdative stress response in aspergilli. Journal of Biological Chemistry 268(40): 35137–35148. 10.1074/jbc.M111.253468 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rüegger A, Kuhn M, et al. (1976) Cyclosporin A, a peptide metabolite from Trichodermapolysporum (LINK ex PERS.) Rifai, with a remarkable immunosuppressive activity. Helvetica Chimica Acta 59: 1075–1092. 10.1002/hlca.19760590412 [DOI] [PubMed] [Google Scholar]
- Rupcic Z, Rascher M, et al. (2018) Two new cyathane diterpenoids from mycelial cultures of the medicinal mushroom Hericiumerinaceus and the rare species, Hericiumflagellum. International Journal of Molecular Science 19: 740. 10.3390/ijms19030740 [DOI] [PMC free article] [PubMed]
- Sahu PK, Ramisetti NR, et al. (2018) An overview of experimental designs in HPLC method development and validation. Journal of Pharmaceutical and Biomedical Analytics 147: 590–611. 10.1016/j.jpba.2017.05.006 [DOI] [PubMed] [Google Scholar]
- Saito K. (1907) Über die Säurebildung bei Aspergillusoryzae. Botanisches Magazin 21: 7–11. 10.15281/jplantres1887.21.240_7 [DOI] [Google Scholar]
- Sampath P, Pollard TD. (1991) Effects of cytochalasin, phalloidin, and pH on the elongation of actin filaments. Biochemistry 30: 1973–1980. 10.1021/bi00221a034 [DOI] [PubMed] [Google Scholar]
- Samson RA, Houbraken JAMP, et al. (2004) New ochratoxin A or sclerotium producing species in AspergillussectionNigri. Studies in Mycology 50: 45–61. [Google Scholar]
- Sandargo B, Thongbai B, et al. (2018) Antiviral 4-hydroxypleurogrisein and antimicrobial pleurotin derivatives from cultures of the nematophagous basidiomycete Hohenbueheliagrisea. Molecules 23: 2697. 10.3390/molecules23102697 [DOI] [PMC free article] [PubMed]
- Sandargo B, Chepkirui C, et al. (2019a) Biological and chemical diversity go hand in hand: Basidiomycota as source of new pharmaceuticals and agrochemicals. Biotechnology Advances 37: 107344. 10.1016/j.biotechadv.2019.01.011 [DOI] [PubMed]
- Sandargo B, Michehl M, et al. (2019b) Antiviral meroterpenoid rhodatin and sesquiterpenoids rhodocoranes A–E from the Wrinkled Peach Mushroom, Rhodotuspalmatus. Organic Letters 21: 3286–3289. 10.1021/acs.orglett.9b01017 [DOI] [PubMed] [Google Scholar]
- Sandargo B, Michehl M, et al. (2019c) Antifungal sesquiterpenoids, rhodocoranes, from submerged cultures of the wrinkled peach mushroom, Rhodotuspalmatus. Journal of Natural Products 83: 720–724. 10.1021/acs.jnatprod.9b00871 [DOI] [PubMed] [Google Scholar]
- Sandargo B, Kaysan L, et al. (2021) Analogs of the carotane antibiotic fulvoferruginin from submerged cultures of a Thai Marasmius sp. Beilstein Journal of Organic Chemisry 17: 1385–1391. 10.3762/bjoc.17.97 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sasaki T, Takagi M, et al. (1992) A new anthelmintic cyclodepsipeptide, PF1022A. Journal of Antibiotics 45: 692–697. 10.7164/antibiotics.45.692 [DOI] [PubMed] [Google Scholar]
- Sauter H, Steglich W, Anke T. (1999) Strobilurins: Evolution of a new class of active substances. Angewandte Chemie Internationale Edition 38: 1328–1349. [DOI] [PubMed] [Google Scholar]
- Scherlach K, Boettger D, et al. (2010) The chemistry and biology of cytochalasans. Natural Product Reports 27(6): 568–886. 10.1039/b903913a [DOI] [PubMed] [Google Scholar]
- Schrey H, Spiteller P. (2019) E- and Z-proxamidines, unprecedented 1,3-diazacyclooct-1-ene alkaloids from fruiting bodies of Laccariaproxima. Chemistry – a European Journal 25(34): 8035–8042. 10.1002/chem.201900566 [DOI] [PubMed] [Google Scholar]
- Schrey H, Backenköhler J, et al. (2019a) Aminotenuazonic acid – Isolation, structure elucidation, total synthesis and herbicidal activity of a new tetramic acid from fruiting bodies of Laccaria species. Chemistry – a European Journal 25(44): 10333–10341. 10.1002/chem.201901405 [DOI] [PubMed] [Google Scholar]
- Schrey H, Müller FJ, et al. (2019b) Nematicidal anthranilic acid derivatives from Laccaria species. Phytochemistry 160: 85–91. 10.1016/j.phytochem.2019.01.008 [DOI] [PubMed] [Google Scholar]
- Schmiedel VM, Hong YJ, et al. (2018) Synthesis and structure revision of dichrocephones A and B. Angewandte Chemie International Edition 57(9): 2419–2422. 10.1002/anie.201711766 [DOI] [PubMed] [Google Scholar]
- Schroeder TE. (1970) The contractile ring. I. Fine structure of dividing mammalian (HeLa) cells and the effects of cytochalasin B. Zeitschrift für Zellforschung und Mikroskopische Anatomie 109: 431–449. 10.1007/BF00343960 [DOI] [PubMed] [Google Scholar]
- Schor R, Cox RJ. (2018) Classic fungal natural products in the genomic age: the molecular legacy of Harold Raistrick. Natural Product Reports 35(3): 230–256. 10.1039/C8NP00021B [DOI] [PubMed] [Google Scholar]
- Schwartz RE, Giacobbe RA, et al. (1989) L671,329, a new antifungal agent. I. Fermentation and isolation. Journal of Antibiotics 42(2): 63–67. 10.7164/antibiotics.42.163 [DOI] [PubMed] [Google Scholar]
- Senior MM, Williamson RT, Martin GE. (2013) Using HMBC and ADEQUATE NMR data to define and differentiate long-range coupling pathways: Is the Crews Rule obsolete? Journal of Natural Products 76(11): 2088–2093. 10.1021/np400562u [DOI] [PubMed]
- Sergey S, Zalesskiy ED, et al. (2014) Miniaturization of NMR systems: desktop spectrometers, microcoil spectroscopy, and “NMR on a Chip” for chemistry, biochemistry, and industry. Chemical Reviews 114(11): 5641–5694. 10.1021/cr400063g [DOI] [PubMed] [Google Scholar]
- Shibata S, Ogihara Y, Ohta A. (1963) Metabolic products of fungi. XXII. On ustilaginoidins. 2. The structure of ostilaginoidin A. Chemical and Pharmaceutical Bulletin 11(9): 1179–1182. 10.1248/cpb.11.1179 [DOI] [PubMed] [Google Scholar]
- Shin HY, Lee JY, et al. (2010) Stimulation of cephalosporin C production in Acremoniumchrysogenum M35 by glycerol. Bioresource Technology 101(12): 4549–4553. 10.1016/j.biortech.2010.01.095 [DOI] [PubMed] [Google Scholar]
- Sica VP, Raja HA, et al. (2014) Mass spectrometry imaging of secondary metabolites directly on fungal cultures. RSC Advances 4(108): 63221–63227. 10.1039/C4RA11564C [DOI] [Google Scholar]
- Sigg HP. (1964) Die Konstitution von Brefeldin A. Helvetica Chimica Acta 47: 1401–1415. 10.1002/hlca.19640470603 [DOI] [Google Scholar]
- Silva DG, Emery FS. (2018) Strategies towards expansion of chemical space of natural product-based compounds to enable drug discovery. Brazilian Journal of Pharmaceutical Science [online] 54(Special): e01004. 10.1590/s2175-97902018000001004 [DOI]
- Singleton VL, Bohonos N. (1964) Chemical characterisation of the mold product decumbin. Agricultural and Biological Chemistry 28(2): 77–81. 10.1271/bbb1961.28.77 [DOI] [Google Scholar]
- Singleton VL, Bohonos N, Ullstrup AJ. (1958) Decumbin, a new compound from a species of Penicillium. Nature 181: 1072–1073. 10.1038/1811072a0 [DOI] [PubMed] [Google Scholar]
- Sir EB, Kuhnert E, et al. (2016) New species and reports of Hypoxylon from Argentina recognized by a polyphasic approach. Mycological Progress 15: 42. 10.1007/s11557-016-1182-z [DOI]
- Skellam E. (2017) The biosynthesis of cytochalasans. Natural Product Reports 34: 1252–1263. 10.1039/C7NP00036G [DOI] [PubMed] [Google Scholar]
- Snider BB, Zhou J. (2006) Synthesis of (+)-Sch 642305 by a biomimetic transannular Michael reaction. Organic Letters 8(7): 1283–1286. 10.1021/ol052948 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Son SY, Lee S, et al. (2018) Comprehensive secondary metabolite profiling toward delineating the solid and submerged-state fermentation of Aspergillusoryzae KCCM 12698. Frontiers in Microbiology 9: 1076. 10.3389/fmicb.2018.01076 [DOI] [PMC free article] [PubMed]
- Spiteller P. (2008) Chemical defence strategies of higher fungi. Chemistry – a Eurpean Journal 14: 9100–9110. 10.1002/chem.200800292 [DOI] [PubMed] [Google Scholar]
- Spiteller P. (2015) Chemical ecology of fungi. Natural Product Reports 32: 971–993. 10.1039/C4NP00166D [DOI] [PubMed] [Google Scholar]
- Spudich J, Lin S. (1972) Cytochalasin B, its interaction with actin and actomyosin from muscle. PNAS 69: 442–446. 10.1073/pnas.69.2.442 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stadler M, Hellwig V. (2004) PCR-based data and secondary metabolites as chemotaxonomic markers in HTS for bioactive compounds from fungi. In: Handbook of Industrial Mycology. CRC Press. 10.1201/9780203970553.ch9 [DOI]
- Stadler M, Fournier J. (2006) Pigment chemistry taxonomy and phylogeny of the Hypoxyloideae (Xylariaceae). Revista Iberoamericana de Micologia 23: 160–170. 10.1016/S1130-1406(06)70037-7 [DOI] [PubMed] [Google Scholar]
- Stadler M, Kolarik M. (2024) Taxol is NOT produced sustainably by endophytic fungi!–A case study for the damage that scientific papermills can cause for the scientific communities. Fungal Biology Reviews 49: 100367. 10.1016/j.fbr.2024.100367 [DOI]
- Stadler M, Fournier J, et al. (2007) Metabolomic studies on the chemical ecology of the Xylariaceae (Ascomycota). Natural Product Communications 2: 287–304. 10.1177/1934578X0700200311 [DOI] [Google Scholar]
- Stadler M, Læssøe T, et al. (2014) A polyphasic taxonomy of Daldinia (Xylariaceae). Studies in Mycology 77: 1–143. 10.3114/sim0016 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Steffan B, Steglich W. (1984) Pigments from the cap cuticle of the bay boletus (Xerocomusbadius). Angewandte Chemie International Edition 23: 445–447. 10.1002/anie.198404451 [DOI] [Google Scholar]
- Steglich W, Furtner W, Prox A. (1970) Variegatorubin, an oxydation product of variegatic acid from Suilluspiperatus and other Boletaceae. Zeitschrift für Naturforschung 25C: 557–558. 10.1515/znb-1970-0529 [DOI]
- Stergiopoulos I, Collemare J, et al. (2013) Phytotoxic secondary metabolites and peptides produced by plant pathogenic Dothideomycetes fungi. FEMS Microbiology Reviews 37(1): 67–93. 10.1111/j.1574-6976.2012.00349.x [DOI] [PubMed] [Google Scholar]
- Sterner O, Bergman R, et al. (1985) The sesquiterpenes of Lactariusvellereus and their role in a proposed chemical defense system. Journal of Natural Products 48: 279. 10.1021/np50038a013 [DOI]
- Stob M, Baldwin RS, et al. (1962) Isolation of an anabolic, uterotrophic compound from corn infected with Gibberellazeae. Nature 196: 1318. 10.1038/1961318a0 [DOI] [PubMed]
- Stoll A. (1918) Zur Kenntnis der Mutterkornalkaloide. Verhandlungen der Naturfreunde-Gesellschaft Basel. 101: 190–191. [Google Scholar]
- Stoll A. (1935) The new ergot alkaloid. Science 82: 415–417. 10.1126/science [DOI] [PubMed] [Google Scholar]
- Stoll DR, Carr PW. (2017) Two-dimensional liquid chromatography: a state of the art tutorial. Analytical Chemistry 89(1): 519–531. 10.1021/acs.analchem.6b03506 [DOI] [PubMed] [Google Scholar]
- Strebhardt K. (2010) Multifaceted polo-like kinases: drug targets and antitargets for cancer therapy. Nature Reviews Drug Discovery 9: 643–660. 10.1038/nrd3184 [DOI] [PubMed] [Google Scholar]
- Strobel G, Stierle A, et al. (1993) Taxomycesandreanae, a proposed new taxon for a bulbilliferous hyphomycete associated with Pacific yew (Taxusbrevifolia). Mycotaxon 47: 71–80. [Google Scholar]
- Stroe MC, Netzker T, et al. (2020) Targeted induction of a silent fungal gene cluster encoding the bacteriaspecific germination inhibitor fumigermin. eLife 9: e52541. 10.7554/eLife.52541 [DOI] [PMC free article] [PubMed]
- Sum Chemutai W, Ebada SS, et al. (2023) Recent progress in the evaluation of secondary metabolites from Basidiomycota. Current Research in Biotechnology 6: 100155. 10.1016/j.crbiot.2023.100155 [DOI]
- Surup F, Narmani A, et al. (2018a) Identification of fungal fossils and novel azaphilone pigments in ancient carbonised specimens of Hypoxylonfragiforme from forest soils of Châtillon-sur-Seine (Burgundy). Fungal Diversity 92(1): 345–356. 10.1007/s13225-018-0412-x [DOI] [Google Scholar]
- Surup F, Kuhnert E, et al. (2018b) The rickiols, 20-, 22-, and 24-membered macrolides from the ascomycete Hypoxylonrickii. Chemistry – e European Journal 24(9): 2200–2213. 10.1002/chem.201704928 [DOI] [PubMed] [Google Scholar]
- Survase SA, Kagliwal LD, et al. (2011) Cyclosporin A – A review on fermentative production, downstream processing and pharmacological applications. Biotechnology Advances 29: 418–435. 10.1016/j.biotechadv.2011.03.004 [DOI] [PubMed] [Google Scholar]
- Superchi S, Scafato P, et al. (2018) Absolute configuration determination by quantum mechanical calculation of chiroptical spectra: Basics and applications to fungal metabolites. Current Medicinal Chemistry 25(2): 287–320. 10.2174/0929867324666170310112009 [DOI] [PubMed] [Google Scholar]
- Ohmori H, Toyama S, Toyama S. (1992) Direct proof that the primary site of action of cytochalasin on cell motility processes is actin. Journal of Cell Biology 116(4): 933–941. 10.1083/jcb.116.4.933 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Takáč T, Pechan T, et al. (2012) Wortmannin treatment induces changes in Arabidopsis root proteome and post-Golgo compartments. Journal of Proteome Research 11: 3127–3142. 10.1021/pr201111n [DOI] [PubMed] [Google Scholar]
- Tareq FS, Hasan CM, et al. (2018) Anti-staphylococcal calopins from fruiting bodies of Caloboletusradicans. Journal of Natural Products 81(2): 400–404. 10.1021/acs.jnatprod.7b00525 [DOI] [PubMed] [Google Scholar]
- Tian D-S, Kuhnert E, et al. (2020) The sporothriolides. A new biosynthetic family of fungal secondary metabolites. Chemical Science 11: 12477–12484. 10.1039/D0SC04886K [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tilburn J, Sarkar S, et al. (1995) The Aspergillus PacC zinc finger transcription factor mediates regulation of both acid- and alkaline-expressed genes by ambient pH. The EMBO Journal 14(4): 779–790. 10.1002/j.1460-2075.1995.tb07056.x [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vadlapudi V, Borah N, et al. (2017) Aspergillus Secondary Metabolite Database, a resource to understand the secondary metabolome of Aspergillus genus. Scientific Reports 7: 7325. 10.1038/s41598-017-07436-w [DOI] [PMC free article] [PubMed]
- Van Goietsenoven G, Mathieu V, et al. (2011) In vitro growth inhibitory effects of cytochalasins and derivatives in cancer cells. Planta Medica 77: 711–717. 10.1055/s-0030-1250523 [DOI] [PubMed] [Google Scholar]
- Vandekerckhove J, Deboben A, et al. (1985) The phalloidin binding site of F-actin. EMBO Journal 4(11): 2815–2818. 10.1002/j.1460-2075.1985.tb04008.x [DOI] [PMC free article] [PubMed] [Google Scholar]
- Veiter L, Rajamanickam V, Herwig C. (2018) The filamentous fungal pellet – relationship between morphology and productivity. Applied Mibrobiology and Biotechnology 102: 2997–3006. 10.1007/s00253-018-8818-7 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Veve MP, Wagner JL. (2018) Lefamulin: Review of a promising novel pleuromutilin antibiotic. Pharmacotherapy 38(9): 935–946. 10.1002/phar.2166 [DOI] [PubMed] [Google Scholar]
- Vijayasarathy S, Prasad P, et al. (2016) C3 and 2D C3 Marfey’s methods for amino acid analysis in natural products. Journal of Natural Products 79: 421–427. 10.1021/acs.jnatprod.5b01125 [DOI] [PubMed] [Google Scholar]
- Vogt E, Künzler M. (2019) Discovery of novel fungal RiPP biosynthetic pathways and their application for the development of peptide therapeutics. Applied Microbiology and Biotechnology 103: 5567–5581. 10.1007/s00253-019-09893-x [DOI] [PubMed] [Google Scholar]
- Volpi C, Orabona C, et al. (2019) Preclinical discovery and development of fingolimod for the treatment of multiple sclerosis, Expert Opinion in Drug Discovery 14: 1199–1212. 10.1080/17460441.2019.1646244 [DOI] [PubMed]
- Vondráček M, Vondrackova J, et al. (1983) Another antibiotic from the basidiomycete Oudemansiellamucida. Collection of Czech Chemical Communications. 48: 1508–1512. 10.1135/cccc19831508 [DOI] [Google Scholar]
- Walsh CT, Tang Y. (2017) Natural Product Biosynthesis: Chemical Logic and Enzymatic Machinery. Royal Society of Chemistry. [ISBN-10:1788010760; ISBN-13: 978-1788010764]
- Walton K, Leier A, Sztul E. (2020) Regulating the regulators: role of phosphorylation in modulating the function of the GBF1/BIG family of Sec7 ARF-GEFs. FEBS Letters 594: 2213–2226. 10.1002/1873-3468.13798 [DOI] [PubMed] [Google Scholar]
- Wang J, Cai Y, et al. (2009) Wortmannin induces homotypic fusion of plant prevacuolar compartments. Journal of Experimental Botany 60(10): 3075–3083. 10.1093/jxb/erp136 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wang K, Lei J, et al. (2012) Bioactive natural compounds from the plant endophytic fungi Pestalotiopsis spp. Mini Reviews in Medicinal Chemistry 12(13): 1382–1393. 10.2174/13895575112091382 [DOI] [PubMed] [Google Scholar]
- Wang C, Hantke V, et al. (2019a) Targeted gene inavtications expose silent cytochalasans in Magnaporthegrisea NI980. Organic Letters 21(11): 4163–4167. 10.1021/acs.orglett.9b01344 [DOI] [PubMed] [Google Scholar]
- Wang C, Becker K, et al. (2019b) Investigating the function of cryptic cytochalasan cytochrome P450 monooxygenase using combinatorial biosynthesis. Organic Letters 21: 8756–8760. 10.1021/acs.orglett.9b03372 [DOI] [PubMed] [Google Scholar]
- Wang WX, Lei X, et al. (2019c) Cytochalasans from the endophytic fungus Xylariacf.curta with resistance reversal activity against fluconazole-resistant Candidaalbicans. Organic Letters 21(4): 1108–1111. 10.1021/acs.orglett.9b00015 [DOI] [PubMed] [Google Scholar]
- Wang C, Lambert C, et al. (2020) Diversely functionalised cytochalasin through mutasynthesis and semi-synthesis. Chemistry – a European Journal 20(60): 13578–13583. 10.1002/chem.202002241 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wasil Z, Pahirulzaman KAK, et al. (2013) One pathway, many compounds: heterologous expression of a fungal biosynthetic pathway reveal its intrinsic potential for diversity. Chemical Science 4: 3845. 10.1039/c3sc51785c [DOI]
- White KN, Amagata T, et al. (2008) Structure revision of spiroleucettadine, a sponge alkaloid with a bicyclic core meager in H-atoms. Journal of Organic Chemistry 73: 8719–8722. 10.1021/jo800960w [DOI] [PMC free article] [PubMed] [Google Scholar]
- Weber RWS, Meffert A, et al. (2005) Production of sordarin and related metabolites by the coprophilous fungus Podosporapleiospora in submerged culture and in its natural substrate. Mycological Research 109(5): 619–626. 10.1017/S0953756205002765 [DOI] [PubMed] [Google Scholar]
- Wehland J, Osborn M, Weber K. (1977) Phalloidin-induced actin polymerization in the cytoplasm of cultures cells interferes with cell locomotion and growth. PNAS 74(12): 5613–5617. 10.1073/pnas.74.12.5613 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wei J, Wu B. (2020) Chemistry and bioactivities of secondary metabolites from the genus Fusarium. Fitoterapia 146: 104638. 10.1016/j.fitote.2020.104638 [DOI] [PubMed]
- Wei X, Feng C, et al. (2019) Enantiomeric polyketides from the starfish-derived symbiotic fungus Penicillium sp. GGF16-1-2. Chemistry and Biodiversity 16(6): e1900052. 10.1002/cbdv.201900052 [DOI] [PubMed]
- Wibberg D, Stadler M, et al. (2021) High quality genome sequences of thirteen Hypoxylaceae (Ascomycota) strengthen the phylogenetic family backbone and enable the discovery of new taxa. Fungal Diversity 106: 7–28. 10.1007/s13225-020-00447-5 [DOI] [Google Scholar]
- Wijayawardene NN, Hyde KD, et al. (2020) Outline of Fungi and fungus-like taxa. Mycosphere 11(1): 1060–1456. 10.5943/mycosphere/11/1/8 [DOI] [Google Scholar]
- Williamson RT, Buevich AV, et al. (2014) LR-HSQMBC: A sensitive NMR technique to probe very longrange heteronuclear coupling pathways. Journal of Organic Chemistry 79(9): 3887–3894. 10.1021/jo500333u [DOI] [PubMed] [Google Scholar]
- Willson J, Amliwala K, et al. (2003) The effect of the anthelmintic emodepside at the neuromuscular junction of the parasitic nematode Ascarissuum. Parasitology 126(1): 79–86. 10.1017/S0031182002002639 [DOI] [PubMed] [Google Scholar]
- Winner M, Gimenez A, et al. (2004) Unusual pulvinic acid dimers from the common fungi Sclerodermacitrinum (Common Earthball) and Chalciporuspiperatus (Peppery Bolete). Angewandte Chemie International Edition 43(13): 1883. 10.1002/anie.200352529 [DOI] [PubMed] [Google Scholar]
- Wipf P, Halter RJ. (2005) Chemistry and biology of wortmannin. Organic and Biomolecular Chemistry 3(11): 2053–2061. 10.1039/b504418a [DOI] [PubMed] [Google Scholar]
- Wittstein K, Rascher M, et al. (2016) Corallocins A-C, Nerve Growth and Brain-Derived Neurotrophic Factor inducing metabolites from the mushroom Hericiumcoralloides. Journal of Natural Products 79(9): 2264–2269. 10.1021/acs.jnatprod.6b00371 [DOI] [PubMed] [Google Scholar]
- Wittstein K, Cordsmeier A, et al. (2020) Identification of Rosellinia species as producers of cyclodepsipeptide PF1022 A and resurrection of the genus Dematophora as inferred from polythetic taxonomy. Studies in Mycology 96: 1–16. 10.1016/j.simyco.2020.01.001 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wolfender JL, Nuzillard JM, et al. (2019) Accelerating metabolite identification in natural product research: Toward an ideal combination of liquid chromatography–high-resolution tandem mass spectrometry and NMR profiling, in silico databases, and chemometrics. Analytical Chemistry 91: 704–742. 10.1021/acs.analchem.8b05112 [DOI] [PubMed] [Google Scholar]
- Wongkanoun S, Chainuwong B, et al. (2023) Studies on the genus Pyrenopolyporus (Hypoxylaceae) in Thailand using a polyphasic taxonomic approach. Journal of Fungi 9: 429. 10.3390/jof9040429 [DOI] [PMC free article] [PubMed]
- Woo P, Lam CW, et al. (2014) The biosynthetic pathway for a thousand-year-old natural food colorant and citrinin in Penicilliummarneffei. Scientific Reports 4: 6728. 10.1038/srep06728 [DOI] [PMC free article] [PubMed]
- World Health Organization (2019) World Health Organization model list of essential medicines: 21st list 2019.
- Wright JLC, McInnes AG, et al. (1970) Structure of sepedonin, a tropolone metabolite of Sepedoniumchrysospermum Fries. Canadian Journal of Chemistry 48(17): 2702–2708. 10.1139/v70-456 [DOI] [Google Scholar]
- Wulf E, Deboben A, et al. (1979) Fluorescent phallotoxin, a tool for the visualizsation of cellular actin. PNAS 76(9): 4498–4502. 10.1073/pnas.76.9.4498 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wymann MP, Bulgarelli-Leva G, et al. (1996) Wortmannin inactivates phosphoinositide 3-kinase by covalent modification of Lys-802, a residue involved in the phosphate transfer reaction. Molecular Cell Biology 16(4): 1722–1733. 10.1128/MCB.16.4.1722 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yahara I, Harada F, et al. (1982) Correlation between effects of 24 different cytochalasins on cellular structures and cellular events and those on actin in vivo. Journal of Cell Biology 92(1): 69–78. 10.1083/jcb.92.1.69 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yan X, Wang L-J, et al. (2016) New on-line separation workflow of microbial metabolites via hyphenation of analytical and preparative comprehensive two-dimensional liquid chromatography. Journal of Chromatography B 2016: 1033–1034. 10.1016/j.jchromb.2016.07.053 [DOI] [PubMed] [Google Scholar]
- Yang YL, Liao WY, et al. (2009) Discovery of new natural products by intact-cell mass spectrometry and LC-SPE-NMR: malbranpyrroles, novel polyketides from thermophilic fungus Malbrancheasulfurea. Chemistry – an European Journal 15(43): 11573–11580. 10.1002/chem.200901556 [DOI] [PubMed] [Google Scholar]
- Yao G, Joswig JO, et al. (2019) Total synthesis of the Death Cap toxin phalloidin: Atropoisomer selectivity explained by molecular-dynamics simulations. Chemistry – a European Journal 25: 8030–8034. 10.1002/chem.201901888 [DOI] [PubMed] [Google Scholar]
- Yu J, Payne GA, et al. (2007) Mycotoxin production and prevention of aflatoxin contamination in food and feed. In: Goldman GH, Osmani SA (Eds) The Aspergilli. Ch. 26. Boca Raton: CRC Press Taylor & Francis. 10.1201/9781420008517-35 [DOI]
- Yu Z, Fischer R. (2019) Light sensing and reponses in fungi. Nature Review Mibrobiology 17: 25–36. 10.1038/s41579-018-0109-x [DOI] [PubMed] [Google Scholar]
- Yabuta T, Sumiki Y. (1938) The crystallization of gibberellins A and B. Journal of the Agricultural Chemical Society of Japan 14: 1526.
- Zeng H, Xie X, et al. (2019) Enantioseparation and determination of triazole fungicides in vegetables and fruits by aqueous two-phase extraction coupled with online heart-cutting two-dimensional liquid chromatography. Food Chemistry 301: 125265. 10.1016/j.foodchem.2019.125265 [DOI] [PubMed]
- Zeng H, Stadler M, et al. (2023) Inhibitory effects of the fungal pigment rubiginosin C on hyphal and biofilm formation in Candidaalbicans and Candidaauris. Journal of Fungi 9(7): 726. 10.3390/jof9070726 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zewail A, Xie MW, et al. (2003) Novel functions of the phosphatidylinositol metabolic pathway discovered by a chemical genomics screen with wortmannin. PNAS Genetics 100(6): 3345–3350. 10.1073/pnas.0530118100 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zhang X, Elliot HMA. (2019) Unlocking the trove of metabolic treasures: activating silent biosynthetic gene clusters in bacteria and fungi. Current Opinions in Microbiology 51: 9–15. 10.1016/j.mib.2019.03.003 [DOI] [PubMed] [Google Scholar]
- Zhang L, Fasoyin OE, et al. (2020) Secondary metabolites from hypocrealean entomopathogenic fungi: novel bioactive compounds. Natural Products Reports 37(9): 1181–1206. 10.1039/C9NP00065H [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zhang Y, Bai J, et al. (2021) Self-resistance in the biosynthesis of fungal macrolides involving cycles of extracellular oxidative activation and intracellular oxidative activation and intracellular reductive inactivation. Angewandte Chemie International Edition 60(12): 6639–6645. 10.1002/anie.202015442 [DOI] [PubMed] [Google Scholar]
- Zhao Y, Su H, et al. (2015) The APSES family proteins in fungi: Characterisations, evolution and functions. Fungal Genetics and Biology 81: 271–280. 10.1016/j.fgb.2014.12.003 [DOI] [PubMed] [Google Scholar]
- Zheng H, Kim J, et al. (2015) Redox metabolites signal polymicrobial biofilm development via the NapA oxidative stress cascade in Aspergillus. Current Biology 25: 29–37. 10.1016/j.cub.2014.11.018 [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zhu H, Chen C, et al. (2021) Progress in the chemistry of cytochalasans. Process in the Chemistry of Organic Natural Products 114: 1–134. 10.1007/978-3-030-59444-2_1 [DOI] [PubMed] [Google Scholar]
- Zuvela P, Skoczylas M, et al. (2019) Column characterization and selection systems in reversed-phase high-performance liquid chromatography. Chemical Reviews 119: 3674–3729. 10.1021/acs.chemrev.8b00246 [DOI] [PubMed] [Google Scholar]
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Data Availability Statement
All of the data that support the findings of this study are available in the main text.