title: Replacement of ParC alpha4 helix with that of GyrA increases the stability and cytotoxicity of topoisomerase IV-quinolone-DNA ternary complexes.
abstract: Replacement of the alpha4 helix of ParC with that of GyrA increased the stability of topoisomerase IV-quinolone-DNA ternary complexes. This mutant topoisomerase IV-mediated cell killing was more efficient than topoisomerase IV-mediated cell killing in Escherichia coli. Thus, the alpha4 helix plays critical roles in determining the stability and the cytotoxicity of ternary complexes.
authors.affiliation: Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA.
authors.forename: Emily S
authors.initials: ES
authors.lastname: Pfeiffer
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hiasa
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology; D003001:Cloning, Molecular; D027081:DNA Gyrase / Q000737:chemistry / Q000235:genetics*; D027101:DNA Topoisomerase IV / Q000737:chemistry* / Q000235:genetics*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics*; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics*; D009154:Mutation / Q000235:genetics; D009643:Norfloxacin / Q000494:pharmacology; D015363:Quinolones / Q000737:chemistry*
chemical_list: D000890:Anti-Infective Agents; D004269:DNA, Bacterial; D015363:Quinolones; D027101:DNA Topoisomerase IV; D027081:DNA Gyrase; D009643:Norfloxacin