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Antibiotic Resistance as a Stress Response: Recovery of High-Level Oxacillin Resistance in Methicillin-Resistant Staphylococcus aureus "Auxiliary" (fem) Mutants by Induction of the Stringent Stress Response.

ABSTRACT: Studies with methicillin-resistant Staphylococcus aureus (MRSA) strain COL have shown that the optimal resistance phenotype requires not only mecA but also a large number of "auxiliary genes" identified by Tn551 mutagenesis. The majority of auxiliary mutants showed greatly increased levels of oxacillin resistance when grown in the presence of sub-MICs of mupirocin, suggesting that the mechanism of reduced resistance in the auxiliary mutants involved the interruption of a stringent stress response, causing reduced production of penicillin-binding protein 2A (PBP 2A).

SUBMITTER: Kim CK

PROVIDER: S-EPMC5527599 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Antibiotic Resistance as a Stress Response: Recovery of High-Level Oxacillin Resistance in Methicillin-Resistant Staphylococcus aureus "Auxiliary" (fem) Mutants by Induction of the Stringent Stress Response.

Kim Choon Keun CK Milheiriço Catarina C de Lencastre Hermínia H Tomasz Alexander A

Antimicrobial agents and chemotherapy 20170725 8

Studies with methicillin-resistant Staphylococcus aureus (MRSA) strain COL have shown that the optimal resistance phenotype requires not only mecA but also a large number of "auxiliary genes" identified by Tn551 mutagenesis. The majority of auxiliary mutants showed greatly increased levels of oxacillin resistance when grown in the presence of sub-MICs of mupirocin, suggesting that the mechanism of reduced resistance in the auxiliary mutants involved the interruption of a str ...[more]

PMID: 28630179

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