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Involvement of Holliday junction resolvase in fluoroquinolone-mediated killing of Mycobacterium smegmatis.

ABSTRACT: The absence of the Holliday-junction Ruv resolvase of Mycobacterium smegmatis increased the bacteriostatic and bactericidal activities of the fluoroquinolone moxifloxacin, an important antituberculosis agent. The treatment of ruvAB-deficient cells with thiourea and 2,2'-bipyridyl lowered moxifloxacin lethality to wild-type levels, indicating that the absence of ruvAB stimulates a lethal pathway involving reactive oxygen species. A hexapeptide that traps the Holliday junction substrate of RuvAB potentiated moxifloxacin-mediated lethality, supporting the development of small-molecule enhancers for moxifloxacin activity against mycobacteria.

SUBMITTER: Long Q

PROVIDER: S-EPMC4325773 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Involvement of Holliday junction resolvase in fluoroquinolone-mediated killing of Mycobacterium smegmatis.

Long Quanxin Q Du Qinglin Q Fu Tiwei T Drlica Karl K Zhao Xilin X Xie Jianping J

Antimicrobial agents and chemotherapy 20141222 3

The absence of the Holliday-junction Ruv resolvase of Mycobacterium smegmatis increased the bacteriostatic and bactericidal activities of the fluoroquinolone moxifloxacin, an important antituberculosis agent. The treatment of ruvAB-deficient cells with thiourea and 2,2'-bipyridyl lowered moxifloxacin lethality to wild-type levels, indicating that the absence of ruvAB stimulates a lethal pathway involving reactive oxygen species. A hexapeptide that traps the Holliday junction substrate of RuvAB p ...[more]

PMID: 25534729

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