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Mutagenesis in the alpha3alpha4 GyrA helix and in the Toprim domain of GyrB refines the contribution of Mycobacterium tuberculosis DNA gyrase to intrinsic resistance to quinolones.

ABSTRACT: The replacement of M74 in GyrA, A83 in GyrA, and R447 in GyrB of Mycobacterium tuberculosis gyrase by their Escherichia coli homologs resulted in active enzymes as quinolone susceptible as the E. coli gyrase. This demonstrates that the primary structure of gyrase determines intrinsic quinolone resistance and was supported by a three-dimensional model of N-terminal GyrA.

SUBMITTER: Matrat S

PROVIDER: S-EPMC2493125 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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Mutagenesis in the alpha3alpha4 GyrA helix and in the Toprim domain of GyrB refines the contribution of Mycobacterium tuberculosis DNA gyrase to intrinsic resistance to quinolones.

Matrat Stéphanie S Aubry Alexandra A Mayer Claudine C Jarlier Vincent V Cambau Emmanuelle E

Antimicrobial agents and chemotherapy 20080421 8

The replacement of M74 in GyrA, A83 in GyrA, and R447 in GyrB of Mycobacterium tuberculosis gyrase by their Escherichia coli homologs resulted in active enzymes as quinolone susceptible as the E. coli gyrase. This demonstrates that the primary structure of gyrase determines intrinsic quinolone resistance and was supported by a three-dimensional model of N-terminal GyrA. ...[more]

PMID: 18426901

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