Hydroxyl radicals are involved in cell killing by the bacterial topoisomerase I cleavage complex.
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.
Liu
I-Fen
IF
Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York 10595, USA.
Annamalai
Thirunavukkarasu
T
Sutherland
Jeanette H
JH
Tse-Dinh
Yuk-Ching
YC
D015082:2,2'-Dipyridyl / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001089:Arabinose / Q000494:pharmacology; D004247:DNA / Q000378:metabolism; D004264:DNA Topoisomerases, Type I / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D017665:Hydroxyl Radical / Q000378:metabolism*; D007502:Iron Chelating Agents / Q000494:pharmacology; D009154:Mutation; D009643:Norfloxacin / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D007502:Iron Chelating Agents; D017665:Hydroxyl Radical; D015082:2,2'-Dipyridyl; D004247:DNA; D001089:Arabinose; D004264:DNA Topoisomerases, Type I; D009643:Norfloxacin