title: MsrR contributes to cell surface characteristics and virulence in Staphylococcus aureus.
abstract: MsrR, a factor contributing to methicillin resistance in Staphylococcus aureus, belongs to the LytR-CpsA-Psr family of cell envelope-associated proteins. Deletion of msrR increased cell size and aggregation, and altered envelope properties, leading to a temporary reduction in cell surface hydrophobicity, diminished colony-spreading ability, and an increased susceptibility to Congo red. The reduced phosphorus content of purified cell walls of the msrR mutant suggested a reduction in wall teichoic acids, which may explain some of the observed phenotypes. Microarray analysis of the msrR deletion mutant revealed only minor changes in the global transcriptome, suggesting that MsrR has structural rather than regulatory functions. Importantly, virulence of the msrR mutant was decreased in a nematode-killing assay as well as in rat experimental endocarditis. MsrR is therefore likely to play a role in cell envelope maintenance, cell separation, and pathogenicity of S. aureus.
authors.affiliation: Institute of Medical Microbiology, University of Zürich, Zürich, Switzerland.
authors.forename: Judith
authors.initials: J
authors.lastname: Hübscher
authors.forename: Nadine
authors.initials: N
authors.lastname: McCallum
authors.forename: Costi D
authors.initials: CD
authors.lastname: Sifri
authors.forename: Paul A
authors.initials: PA
authors.lastname: Majcherczyk
authors.forename: José M
authors.initials: JM
authors.lastname: Entenza
authors.forename: Roni
authors.initials: R
authors.lastname: Heusser
authors.forename: Brigitte
authors.initials: B
authors.lastname: Berger-Bächi
authors.forename: Patricia
authors.initials: P
authors.lastname: Stutzmann Meier
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001422:Bacterial Adhesion; D017173:Caenorhabditis elegans / Q000382:microbiology; D002473:Cell Wall / Q000502:physiology* / Q000648:ultrastructure*; D004697:Endocarditis, Bacterial / Q000382:microbiology / Q000473:pathology; D017353:Gene Deletion; D020869:Gene Expression Profiling; D057927:Hydrophobic and Hydrophilic Interactions; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008826:Microbial Sensitivity Tests; D020411:Oligonucleotide Array Sequence Analysis; D051381:Rats; D013203:Staphylococcal Infections / Q000382:microbiology / Q000473:pathology; D013211:Staphylococcus aureus / Q000187:drug effects / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity*; D013499:Surface Properties; D014774:Virulence
chemical_list: D000900:Anti-Bacterial Agents; D008565:Membrane Proteins; C477297:MsrR protein, Staphylococcus aureus