title: Lack of a functional methionine sulfoxide reductase (MsrB) increases oxacillin and H₂O₂ stress resistance and enhances pigmentation in Staphylococcus aureus.
abstract: Staphylococcus aureus produces 3 MsrA enzymes (MsrA1, MsrA2, and MsrA3) and 1 MsrB enzyme. The genes encoding MsrA1 and MsrB are the first and second genes of a 4-gene operon in S. aureus. In a previous study, MsrA1-deficient S. aureus cells showed increased sensitivity to oxidative stress conditions in spite of a higher production of MsrB. In this study, an msrB mutant of S. aureus was created by site-directed mutagenesis that left the first gene of this locus, msrA1, intact. Studies with this mutant suggest that a deletion of MsrB increases resistance of S. aureus to H2O2 and oxacillin and that the mutant cells produce a higher level of carotenoids relative to wild-type S. aureus cells.
authors.affiliation: Microbiology and Immunology, Kirksville College of Osteopathic Medicine, A.T. Still University of Health Sciences, 800 West Jefferson Street, Kirksville, MO 63501, USA.
authors.forename: Vineet K
authors.initials: VK
authors.lastname: Singh
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics*; D017353:Gene Deletion; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D051150:Methionine Sulfoxide Reductases / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D016297:Mutagenesis, Site-Directed; D010068:Oxacillin / Q000494:pharmacology*; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress; D010858:Pigmentation; D013211:Staphylococcus aureus / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D016877:Oxidants; D006861:Hydrogen Peroxide; D051150:Methionine Sulfoxide Reductases; C027219:methionine sulfoxide reductase; D010068:Oxacillin
keywords: H2O2 stress; MsrB; Staphylococcus aureus; oxacillin stress; stress oxydatif; stress par les antibiotiques