title: Mechanism of reduced vancomycin susceptibility conferred by walK mutation in community-acquired methicillin-resistant Staphylococcus aureus strain MW2.
abstract: Point mutations with unclear molecular mechanisms are often associated with vancomycin resistance in Staphylococcus aureus. Here, we observed that the walK (G223D) mutation caused decreased expression of genes associated with cell wall metabolism, decreased autolytic activity, thickened cell walls, and reduced vancomycin susceptibility. A phosphorylation assay showed that WalK (G223D) exhibited reduced autophosphorylation, which led to reduced phosphorylation of WalR. An electrophoretic mobility shift assay indicated that WalK (G223D)-phosphorylated WalR had a reduced capacity to bind to the atlA promoter.
authors.affiliation: Department of Microbiology and Immunology and CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences and Medical Center, University of Science & Technology of China, Hefei, Anhui, China.
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Hu
authors.affiliation: Department of Microbiology and Immunology and CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences and Medical Center, University of Science & Technology of China, Hefei, Anhui, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Microbiology and Immunology and CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences and Medical Center, University of Science & Technology of China, Hefei, Anhui, China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Microbiology and Immunology and CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences and Medical Center, University of Science & Technology of China, Hefei, Anhui, China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Chen
authors.affiliation: Department of Microbiology and Immunology and CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Life Sciences and Medical Center, University of Science & Technology of China, Hefei, Anhui, China Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui, China sunb@ustc.edu.cn.
authors.forename: Baolin
authors.initials: B
authors.lastname: Sun
mesh_terms: D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D009154:Mutation; D010766:Phosphorylation; D011401:Promoter Regions, Genetic / Q000235:genetics; D013211:Staphylococcus aureus / Q000187:drug effects; D014640:Vancomycin / Q000494:pharmacology*
chemical_list: D014640:Vancomycin