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A mecA-negative strain of methicillin-resistant Staphylococcus aureus with high-level ?-lactam resistance contains mutations in three genes.

ABSTRACT: We previously generated a ceftobiprole-resistant Staphylococcus aureus strain after high inoculum serial passage of a mecA-negative variant of strain COL (R. Banerjee, M. Gretes, L. Basuino, N. Strynadka, and H. F. Chambers, Antimicrob. Agents Chemother. 52:2089-2096, 2008). Genome resequencing of this strain, CRB, revealed that it differs from its parent by five single-nucleotide polymorphisms in three genes, specifically, those encoding PBP4, a low-molecular-weight penicillin-binding protein, GdpP, a predicted signaling protein, and AcrB, a cation multidrug efflux transporter. CRB displayed resistance to a variety of ?-lactams but was hypersusceptible to cefoxitin.

SUBMITTER: Banerjee R

PROVIDER: S-EPMC2976154 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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A mecA-negative strain of methicillin-resistant Staphylococcus aureus with high-level β-lactam resistance contains mutations in three genes.

Banerjee Ritu R Gretes Michael M Harlem Christopher C Basuino Li L Chambers Henry F HF

Antimicrobial agents and chemotherapy 20100830 11

We previously generated a ceftobiprole-resistant Staphylococcus aureus strain after high inoculum serial passage of a mecA-negative variant of strain COL (R. Banerjee, M. Gretes, L. Basuino, N. Strynadka, and H. F. Chambers, Antimicrob. Agents Chemother. 52:2089-2096, 2008). Genome resequencing of this strain, CRB, revealed that it differs from its parent by five single-nucleotide polymorphisms in three genes, specifically, those encoding PBP4, a low-molecular-weight penicillin-binding protein, ...[more]

PMID: 20805396

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