title: The proline-rich peptide Bac7(1-35) reduces mortality from Salmonella typhimurium in a mouse model of infection.
abstract: BACKGROUND
  Bac7 is a proline-rich peptide with a potent in vitro antimicrobial activity against Gram-negative bacteria. Here we investigated its activity in biological fluids and in vivo using a mouse model of S. typhimurium infection.
  
  
  RESULTS
  The efficacy of the active 1-35 fragment of Bac7 was assayed in serum and plasma, and its stability in biological fluids analyzed by Western blot and mass spectrometry. The ability of the peptide to protect mice against Salmonella was assayed in a typhoid fever model of infection by determination of survival rates and bacterial load in liver and spleen of infected animals. In addition, the peptide's biodistribution was evaluated by using time-domain optical imaging. Bac7(1-35) retained a substantial in vivo activity showing a very low toxicity. The peptide increased significantly the number of survivors and the mean survival times of treated mice reducing the bacterial load in their organs despite its rapid clearance.
  
  
  CONCLUSIONS
  Our results provide a first indication for a potential development of Bac7-based drugs in the treatment of salmonellosis and, eventually, other Gram-negative infections. The in vivo activity for this peptide might be substantially enhanced by decreasing its excretion rate or modifying the treatment schedule.
authors.affiliation: Department of Life Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy. mbenincasa@units.it
authors.forename: Monica
authors.initials: M
authors.lastname: Benincasa
authors.forename: Chiara
authors.initials: C
authors.lastname: Pelillo
authors.forename: Sonia
authors.initials: S
authors.lastname: Zorzet
authors.forename: Chiara
authors.initials: C
authors.lastname: Garrovo
authors.forename: Stefania
authors.initials: S
authors.lastname: Biffi
authors.forename: Renato
authors.initials: R
authors.lastname: Gennaro
authors.forename: Marco
authors.initials: M
authors.lastname: Scocchi
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides / Q000493:pharmacokinetics / Q000494:pharmacology*; D008099:Liver / Q000382:microbiology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008808:Mice, Inbred CBA; D012481:Salmonella Infections, Animal / Q000188:drug therapy* / Q000382:microbiology; D012486:Salmonella typhimurium; D013154:Spleen / Q000382:microbiology; D014018:Tissue Distribution
chemical_list: D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; C481640:Bac7(1-35) peptide