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Hydroxyl radicals are involved in cell killing by the bacterial topoisomerase I cleavage complex.

ABSTRACT: Escherichia coli expressing SOS-inducing mutant topoisomerase I was utilized to demonstrate that covalent protein-DNA complex accumulation results in oxidative damage. Hydroxyl radicals were detected following mutant topoisomerase induction. The presence of the Fe(2+) chelator 2,2'-dipyridyl and an iscS mutation affecting Fe-S cluster formation protect against topoisomerase I cleavage complex-mediated cell killing.

SUBMITTER: Liu IF

PROVIDER: S-EPMC2725605 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Hydroxyl radicals are involved in cell killing by the bacterial topoisomerase I cleavage complex.

Liu I-Fen IF Annamalai Thirunavukkarasu T Sutherland Jeanette H JH Tse-Dinh Yuk-Ching YC

Journal of bacteriology 20090612 16

Escherichia coli expressing SOS-inducing mutant topoisomerase I was utilized to demonstrate that covalent protein-DNA complex accumulation results in oxidative damage. Hydroxyl radicals were detected following mutant topoisomerase induction. The presence of the Fe(2+) chelator 2,2'-dipyridyl and an iscS mutation affecting Fe-S cluster formation protect against topoisomerase I cleavage complex-mediated cell killing. ...[more]

PMID: 19525344

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