Table 6.
Contributions of modified filamentous phages in detection and control of pathogens in environment
| Filamentous phage | Modification in filamentous phage | Biosensor type and working principle | Target biomaterial | Sensitivity/specificity | References |
|---|---|---|---|---|---|
| Phages in theory of environmental sensing: As an agent to develop sensitive biosensor to track pathogens | |||||
| E2 from fd and 7b1 from M13 phage libraries | Expression of Salmonella typhimurium‐specific peptide (VTPPTQHQ) on pVIII | Quartz crystal microbalance (QCM):Modified phage immobilized on QCM platform detects the pathogen based on Piezoelectric effect. | Salmonella typhimurium | Detects 102 cells/ml with a response time of <180 s | Olsen et al. (2007) |
| JRB7, clone from f8/8 landscape phage library | Expression of B. antracis‐specific peptide on pVIII | Magnetoelastic resonators (ME):Recombinant phage immobilized onto ME platform coated with gold surface binds to antigen | B. anthracis spores | Detects 103 spores/ml in vitro conditions | Shen, Lakshmanan, Mathison, Petrenko, and Chin (2009) |
| E2 derived from fd landscape phage library | Expression of S. typhimurium‐specific peptide on pVIII | Magnetoelastic resonators (ME):Phage nanoprobe immobilized on ME detects binding of pathogen as decrease in resonance frequency | S. typhimurium | Detects 5×102 cfu/ml of pathogen on the surface of tomato | Li, Johnson, et al. (2010), Li, Li, et al. (2010) |
| M13 | M13 displaying peptide specific to target pathogen | Lithographically patterned nanowire‐electrodeposition (LPNE):Virus functionalized nanowires developed by grafting modified phage on poly 3,4‐ethylenedioxythiophene (PEDOT) would bind specific antigen. | Specific antigen on targeted pathogen | Detects antigen (20 nM–99 nM) in in vitro and in vivo conditions | Arter, Taggart, Mclntire, Penner, and Weiss (2010) |
| M13 (Phagemid M13KO7) | Expression of the reporter gene, alkaline phosphatase on pVIII with the help of helper phage M13KO7 | Amperometric Electrochemical Biosensors:Phage immobilized on the electrode detects the target organism in environmental samples based on the activity of reporter enzyme | E. coliTG1 | Detection of 1 cfu/ml in <3 hr; 10‐fold increase in the sensitivity of the biosensor (due to enzyme activity) as compared to other phage‐based biosensors | Neufeld et al. (2005) |
| M13 | Expression of prostate‐specific membrane antigen (PSMA) specific peptide (CALCEF ‐LG) on pVIII | Electrochemical impedance spectroscopy (EIS): Electrode developed by covalent binding of phage to the gold surface generates electrical signal on binding of antigen | PSMA | 120 nM of the target protein | Yang et al. (2006) |
| M13 | pH‐responsive cyanine dye (HCyC‐646) is covalently attached to pVIII | Near Infrared Fluorescence Ratiometric pH Imaging: A bright pH‐responsive ratiometric imaging platform, developed by ligation of dye to the phage surface, measures the emission signal on pH change | Optically diffused tissue | Pathogenesis associated changes in acid–base homeostasis are analyzed by pH measurements both intracellularly and through optically diffused tissue2008 | Hilderbrand et al. (2008) |
| Modified M13 | Modified pIII binds specifically to target antigens, whereas modified pVIII reacts with signal‐producing gold nanoparticles (Au NPs) | Single bioanalytical platform for antigen detection and identification:DNA‐conjugated phage detects (optically/spectroscopically) and identifies the antigen (DNA microarray) | Protein detection and identification | Real time, reagent free detection of antigen (detection limit 25 fmole) and its identification in a high‐throughput manner | Lee, Domaille, and Cha (2012) |
| R5C2 | Expression of streptavidin‐binding peptide NH2–ANRLP CHPQFPCTSHE on pVIII | Opto‐fluidic ring resonator (OFRR) – Lab‐on‐Chip device:Phage integrated on OFRR platform acts as a receptor for detection of analyte and enables label‐free detection of the analyte in small volume | Protein/DNA/Virus | Real‐time detection of protein/DNA (100 pM; Kdapparent 25 pM) and virus particles (2.3 × 103 pfu/ml) | Zhu et al. (2008) |
| A clone from f8/8 landscape phage library | Expression of EPRLSPHS peptide on pVIII protein | Modified phage displaying unique landscape on its body binds antigen with extremely high efficiency and specificity | Spores of Bacillus anthracis | Up to 70‐fold high specificity to spores of B. anthracis than other Bacillusspp. | Brigati et al. (2004) |
| Phages in theory of antagonism and biocontrol: As an agent to biocontrol of phytopathogens | |||||
| M13 | Phages encode restriction endonuclease BglII gene (M13R) or λS holin gene (M13S105, M13VIIIS105) | Genetically modified (GM) phage as bactericidal agents: Modified phage kills bacterial host without lysis and release of toxin in environment | E. coli strain MC4100F¢ | >99% killing of pathogen within 2 hr | Hagens and Bläsi (2003) |
| Pf3 | Phage export protein gene is replaced with BglII endonuclease gene | Nonreplicating GM phage as bactericidal agents:Modified phage kills host bacteria without lysis and release of endotoxins | Pseudomonas aeruginosa | Phage treatment effectively control P. aeruginosa population in in vivo condition with a minimal lethal dose | Hagens, Habel, von Ahsen, von Gabain, and Blasi (2004) |
| Nonlytic, M13 phagemid | Encode the addiction toxins modules (Gef and ChpBK) | Recombinant Phage as a Lethal‐Agent Delivery Vehicle:Modified phage delivers addiction toxins module to elicit programmed cell death in bacterial host | E. coli ER2738 | 94%–98% reduction in in vivo condition within 5 hr | Westwater et al. (2003) |
| M13mp18 phage | Expression of genes (csrA and ompF) that target multiple antibiotics simultaneously | Adjuvant therapy to treat antibiotic‐resistant bacteria:Modified phages trigger SOS and non‐SOS gene networks that are not directly targeted by antibiotics (e.g., aminoglycosides and β‐lactams) kills antibiotic‐resistant bacteria, biofilm cells, and persister cells | E. coli EMG2 and RFS289 | Modified phage kills antibiotic‐resistant bacteria, biofilm cells, and persister cells | Lu and Collins (2009) |
| M13 | Predominant expression of three glutamic acid (E3) residues on pVIII | Silverized Antimicrobial Phage Fibers: Modified phages immobilized to the fibers electrostatically bind silver ions which on subsequent reduction to metallic silver provide antibacterial properties to the fibers | Staphylococcus epidermidis and E. coli | Biocidal fibers show bactericidal activity up to 300 □m distance within a 2 hr exposure; kills 109 cfu/ml with 20 hr continued exposure | Mao, Belcher, and Van Vliet (2010) |
| fRSM (φRSM1 or φRSM3) | Phages found in natural association with host bacteria R. solanacearum MAFF 106603 and MAFF106611 | Phage therapy reduces virulence of phytopathogen: Phage‐infected host cells are characterized with reduction in: (i) twitching motility; (ii) number of type IV pili (Tfp); (iii) β‐1,4‐endoglucanase (Egl) activity; (iv) extracellular polysaccharide (EPS) production, and (iii) expression of certain genes (egl, pehC, phcA, phcB, pilT, and hrpB). | R. solanacearum MAFF 106603 and MAFF 106611 | Loss of virulence to cause wilting to tomato plant (105 cfu wild type trigger wilting within 3 days and cause plant death within 5–7 days) | Addy et al. (2012a) |
| φXacF1 | Phage found in natural association with host bacteria X. axonopodis pv. citri MAFF673010 and MAFF301080 | Phage therapy reduces virulence of pathogen:φXacF1‐infected X. axonopodis pv. citri strains are characterized with lower levels of extracellular polysaccharide production, reduced twitching motility, slower growth rate, and a dramatic reduction in virulence. | X. axonopodis pv. citri MAFF673010 and MAFF301080 | Extreme reduction in virulence, failed to cause citrus canker in lemon even after 4 weeks of post‐infection | Ahmad et al. (2014) |