title: Antimicrobial factor from Bacillus amyloliquefaciens inhibits Paenibacillus larvae, the causative agent of American foulbrood.
abstract: Bacillus amyloliquefaciens LBM 5006 produces an antimicrobial factor active against Paenibacillus larvae, a major honeybee pathogen. The antagonistic effect and the mode of action of the antimicrobial factor were investigated. The antibacterial activity was produced starting at mid-logarithmic growth phase, reaching its maximum during the stationary phase. Exposure of cell suspensions of P. larvae to this antimicrobial resulted in loss of cell viability and reduction in optical density associated with cell lysis. Scanning electron microscopy showed damaged cell envelope and loss of protoplasmic material. The antimicrobial factor was stable for up to 80°C, but it was sensitive to proteinase K and trypsin. Mass spectrometry analysis indicates that the antimicrobial activity is associated with iturin-like peptides. The antimicrobial factor from B. amyloliquefaciens LBM 5006 showed a bactericidal effect against P. larvae cells and spores. This is the first report on iturin activity against P. larvae. This antimicrobial presents potential for use in the control of American foulbrood disease.
authors.affiliation: Laboratório de Bioquímica e Microbiologia Aplicada, Instituto de Ciência e Tecnologia de Alimentos, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Lisianne Brittes
authors.initials: LB
authors.lastname: Benitez
authors.forename: Renata Voltolini
authors.initials: RV
authors.lastname: Velho
authors.forename: Amanda
authors.initials: A
authors.lastname: de Souza da Motta
authors.forename: Jéferson
authors.initials: J
authors.lastname: Segalin
authors.forename: Adriano
authors.initials: A
authors.lastname: Brandelli
mesh_terms: D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology*; D001407:Bacillus / Q000737:chemistry*; D001516:Bees / Q000382:microbiology*; D007814:Larva / Q000254:growth & development / Q000382:microbiology; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D008855:Microscopy, Electron, Scanning; D056507:Paenibacillus / Q000187:drug effects* / Q000648:ultrastructure; D010456:Peptides, Cyclic / Q000494:pharmacology*; D013172:Spores, Fungal / Q000187:drug effects
chemical_list: D000935:Antifungal Agents; D010456:Peptides, Cyclic; C013579:iturin A