期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2012
卷号:109
期号:46
页码:18909-18914
DOI:10.1073/pnas.1209126109
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Staphylococcus aureus peptidoglycan (PG) is densely functionalized with anionic polymers called wall teichoic acids (WTAs). These polymers contain three tailoring modifications: D-alanylation, -O-GlcNAcylation, and {beta}-O-GlcNAcylation. Here we describe the discovery and biochemical characterization of a unique glycosyltransferase, TarS, that attaches {beta}-O-GlcNAc ({beta}-O-N-acetyl-D-glucosamine) residues to S. aureus WTAs. We report that methicillin resistant S. aureus (MRSA) is sensitized to {beta}-lactams upon tarS deletion. Unlike strains completely lacking WTAs, which are also sensitive to {beta}-lactams, {Delta}tarS strains have no growth or cell division defects. Because neither -O-GlcNAc nor {beta}-O-Glucose modifications can confer resistance, the resistance phenotype requires a highly specific chemical modification of the WTA backbone, {beta}-O-GlcNAc residues. These data suggest {beta}-O-GlcNAcylated WTAs scaffold factors required for MRSA resistance. The {beta}-O-GlcNAc transferase identified here, TarS, is a unique target for antimicrobials that sensitize MRSA to {beta}-lactams.