Hydroxyl radicals are involved in cell killing by the bacterial topoisomerase I cleavage complex.
نویسندگان
چکیده
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.
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عنوان ژورنال:
- Journal of bacteriology
دوره 191 16 شماره
صفحات -
تاریخ انتشار 2009