Table 1.
Microbiota-derived tryptophan metabolites and gut microbiota (↑ represents an increase, ↓ represents a decrease).
| Tryptophan Metabolism |
Producers | Diet Influence |
Impact on Metabolism |
Impact on Microbes | Reference |
|---|---|---|---|---|---|
| Indole | Bacteroides thetaiotaomicron | High-fat diet | Indole Production↓ |
Bacteroides spp.↓ Escheichia coli↑ Clostridium↓ |
[11,31,32] |
| Bacteroides ovatus | |||||
| Clostridium limosum | |||||
| Clostridium bifermentans | |||||
| Clostridium malenomenatum | |||||
| Clostridium lentoputrescens | |||||
| Clostridium tetani | |||||
| Clostridium tetanomorphum | |||||
| Enterococcus faecalis | |||||
| Escheichia coli | |||||
| Fusobacterium nucleatum | |||||
| Haemophilus influenza | |||||
| Proteus vulgaris | |||||
| Paracolobactrumcoliforme | |||||
| Salmonella enterica | |||||
| …for more see [33] | |||||
| Indole-3-acetic acid (IAA) | Bacteroides thetaiotaomicron | High-fat diet | IAA Production↓ |
Bifidobacterium spp.↓ Bacteroides↓ Bifidobacterium adolescentis↓ |
[31,34,35,36,37,38] |
| Bacteroides ovatus | |||||
| Bacteroides fragilis | |||||
| Bifidobacterium adolescentis | |||||
| Bifidobacterium pseudolongum | |||||
| Clostridium difficile | |||||
| Clostridium lituseburense | High-fiber diet | IAA Production↑ |
Bifidobacteriumadolescentis↑ Clostridium difficile↓ |
||
| Clostridium sporogenes | |||||
| Escherichia coli | |||||
| Eubacterium hallii | |||||
| Eubacterium cylindroides | |||||
| …for more see [39] | |||||
| Indole-3-acrylic acid (IA) | Clostridium sporogenes | High-fiber diet | IA production ↑ |
Parabacteroides distasonis↑ | [40,41] |
| Peptostreptococcusrussellii | |||||
| Peptostreptococcusanaerobius | |||||
| Peptostreptococcusstomatis | |||||
| Parabacteroides distasonis | |||||
| …for more see [42] | |||||
| Indole-3-propionic acid (IPA) | Clostridium sporogenes | High-fat diet | IPA Production↓ |
Clostridiumsporogenes↓ | [43,44,45,46,47,48,49,50] |
| Clostridium caloritolerans | |||||
| Clostridium botulinum | High-fiber diet | IPA Production↑ |
Clostridium↑ Bifidobacterium↑ Lactobacillus↑ Peptostreptococcus↑ |
||
| Peptostreptococcusasaccharolyticus | |||||
| Peptostreptococcusrussellii | |||||
| PeptostreptococcusanaerobiusCC14N | |||||
| Peptostreptococcusstomatis | Ketogenic diet | IPA Production↓ |
Lactobacillus murinus ↓ | ||
| …for more see [51] | |||||
| Indole-3-lactic acid (ILA) | Anaerostipeshadrus | High-fat diet | ILA Production↓ |
Eubacterium↓ Eubacterium rectale↓ Anaerostipescaccae↓ Bifidobacterium adolescentis↓ |
[37,52] |
| Anaerostipescaccae | |||||
| Bacteroides thetaiotaomicron | |||||
| Bacteroides eggerthii | |||||
| Bacteroides ovatus | |||||
| Bifidobacterium adolescentis | |||||
| Bifidobacterium bifidum | |||||
| Bifidobacterium pseudolongum | |||||
| Clostridium bartlettii | |||||
| Clostridium sporogenes | |||||
| Escherichia coli | High-fiber diet | ILA Production↑ |
Lactobacillus↑ Megamonas↑ |
||
| Eubacterium rectale | |||||
| Eubacterium cylindroides | |||||
| Faecalibacteriumprausnitzii | |||||
| Lactobacillus murinus | |||||
| Lactobacillus paracasei | |||||
| Lactobacillus reuteri | |||||
| Megamonas hypermegale | |||||
| … for more see [53] | |||||
| Indole-3-aldehyde(IAld) | Lactobacillus johnsonii | High-fiber diet | IAId Production↑ |
Lactobacillus↑ | [54] |
| Lactobacillusreuteri | |||||
| Lactobacillusacidophilus | |||||
| Lactobacillusgallinarum | |||||
| … for more see [30] | |||||
| Indole-3-acetaldehyde (IAAld) | Escherichia coli | / | / | / | [55] |
| Tryptamine | Firmicutes C. sporogenes | High-fat diet | Tryptamine↓ |
Bacteroides↓ Escheichia coli↑ |
[52,56] |
| Clostridium sporogenes | |||||
| Escherichia. coli | |||||
| Ruminococcusgnavus | |||||
| Bacteroides | |||||
| 3-methylindole (skatole) | Bacteroides thetaiotaomicron | High-fat diet | complex manner |
/ | [57,58] |
| Butyrivibriofibrisolvens | |||||
| Clostridium bartlettii | |||||
| Clostridium drakei | |||||
| Eubacterium rectale | |||||
| Megamonas hypermegale | |||||
| Parabacteroides distasonis | |||||
| … for more see [57] |