title: Friend or foe? Antimicrobial peptides trigger pathogen virulence.
abstract: In an age of antibiotic-resistant pathogens, antimicrobial peptides have emerged as novel therapeutics hailed for their bactericidal and immunomodulatory properties. However, a recent paper by Bader et al. demonstrates that these molecules also trigger bacteria to arm themselves against host immune responses. The authors show that the two-component regulatory system PhoP-PhoQ of Salmonella is activated not only in cation-deficient environments as previously thought, but also by binding to antimicrobial peptides, thus promoting gene transcription necessary for Salmonella survival within the host. Thus, the antimicrobial peptide might be a double-edged sword, promoting antibacterial immunity while simultaneously triggering pathogen virulence.
authors.affiliation: Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Bishop
authors.forename: B Brett
authors.initials: BB
authors.lastname: Finlay
mesh_terms: D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000627:therapeutic use / Q000633:toxicity*; D001426:Bacterial Proteins / Q000502:physiology; D006801:Humans; D008954:Models, Biological; D012475:Salmonella / Q000187:drug effects* / Q000472:pathogenicity* / Q000502:physiology; D015398:Signal Transduction; D014774:Virulence / Q000187:drug effects
chemical_list: D023181:Antimicrobial Cationic Peptides; D001426:Bacterial Proteins; C079792:PhoQ protein, Bacteria; C061064:PhoP protein, Bacteria