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SbcCD-mediated processing of covalent gyrase-DNA complex in Escherichia coli.

ABSTRACT: Quinolones trap the covalent gyrase-DNA complex in Escherichia coli, leading to cell death. Processing activities for trapped covalent complex have not been characterized. A mutant strain lacking SbcCD nuclease activity was examined for both accumulation of gyrase-DNA complex and viability after quinolone treatment. Higher complex levels were found in ?sbcCD cells than in wild-type cells after incubation with nalidixic acid and ciprofloxacin. However, SbcCD activity protected cells against the bactericidal action of nalidixic acid but not ciprofloxacin.

SUBMITTER: Aedo S

PROVIDER: S-EPMC3811449 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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SbcCD-mediated processing of covalent gyrase-DNA complex in Escherichia coli.

Aedo Sandra S Tse-Dinh Yuk-Ching YC

Antimicrobial agents and chemotherapy 20130805 10

Quinolones trap the covalent gyrase-DNA complex in Escherichia coli, leading to cell death. Processing activities for trapped covalent complex have not been characterized. A mutant strain lacking SbcCD nuclease activity was examined for both accumulation of gyrase-DNA complex and viability after quinolone treatment. Higher complex levels were found in ΔsbcCD cells than in wild-type cells after incubation with nalidixic acid and ciprofloxacin. However, SbcCD activity protected cells against the b ...[more]

PMID: 23917316

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