title: Insights into aureocin A70 regulation: participation of regulator AurR, alternative transcription factor σ(B) and phage ϕ11 regulator cI.
abstract: Aureocin A70 is a four-component bacteriocin produced by Staphylococcus aureus A70. Its locus encompasses three transcriptional units coding for: (i) structural peptides (aurABCD), (ii) an ABC transporter (aurT) and (iii) the dedicated immunity protein and a putative transcriptional regulator (aurRI). The data provided here showed that AurR is an HTH-containing protein that reduces aureocin A70 production on solid medium, but not in broth. AurR seems to work similarly to LtnR and CylR2, repressors of lantibiotics lacticin 3147 and cytolysin, respectively. At least two other factors play a role in aureocin A70 production: (i) the alternative σ(B) factor, as σ(B)-defective cells produce more bacteriocin than the restored σ(B+) cells, and (ii) the ϕ11 regulator cI, since a lysogenic strain for ϕ11 exhibited a significant reduction in aureocin A70 production on solid medium when compared with the non-lysogenic isogenic strain. Full aeration and ROS generation abolished the effect of the phage regulators on aureocin A70 production. Interestingly, the ϕ11 regulator cI seems to cooperate with AurR to abolish aureocin A70 production. This study therefore represents the first report showing that phage regulators may play a role in regulation of bacteriocin production.
authors.affiliation: Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, UFRJ, Rio de Janeiro, Brazil; Instituto Nacional da Propriedade Industrial, INPI, Brazil. Electronic address: mcvarella@gmail.com.
authors.forename: Marcus Lívio Varella
authors.initials: ML
authors.lastname: Coelho
authors.affiliation: Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, UFRJ, Rio de Janeiro, Brazil. Electronic address: lfleming@hotmail.com.
authors.forename: Luana Rocha
authors.initials: LR
authors.lastname: Fleming
authors.affiliation: Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, UFRJ, Rio de Janeiro, Brazil. Electronic address: carminhafbastos@gmail.com.
authors.forename: Maria do Carmo de Freire
authors.initials: Mdo C
authors.lastname: Bastos
mesh_terms: D001430:Bacteriocins / Q000096:biosynthesis*; D015964:Gene Expression Regulation, Bacterial; D008242:Lysogeny; D013204:Staphylococcus Phages; D013211:Staphylococcus aureus / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D014764:Viral Proteins / Q000378:metabolism*
chemical_list: D001430:Bacteriocins; D014157:Transcription Factors; D014764:Viral Proteins; C435363:aureocin A70
keywords: Antimicrobial peptide; Bacteriocin; Phage regulators; Regulation; Staphylococcus aureus; σ(B)