title: Effect of DNA gyrase inhibitors pefloxacin, five other quinolones, novobiocin, and clorobiocin on Escherichia coli topoisomerase I.
abstract: Two coumarins, inhibitors of the B subunit of DNA gyrase, and six quinolones, inhibitors of the A subunit, were tested against Escherichia coli topoisomerase I-catalyzed DNA relaxation. Coumarins had no effect, whereas quinolones were inhibitors of the enzyme. This inhibition was compared with that of DNA gyrase and calf thymus topoisomerase I. The 50% inhibitory concentrations for E. coli topoisomerase I were about one order of magnitude higher than the corresponding values for E. coli DNA gyrase but were far lower than the known values for calf thymus topoisomerase I. There was a good relationship between inhibition of the two prokaryotic topoisomerases and MICs for E. coli, and the quinolones could be ranked in the same order in the three cases.
authors.affiliation: Centre d'Etudes et de Recherche en Chimie Organique Appliquée, Centre National de la Recherche Scientifique, Thiais, France.
authors.forename: X
authors.initials: X
authors.lastname: Tabary
authors.forename: N
authors.initials: N
authors.lastname: Moreau
authors.forename: C
authors.initials: C
authors.lastname: Dureuil
authors.forename: F
authors.initials: F
authors.lastname: Le Goffic
mesh_terms: D004587:Electrophoresis, Agar Gel; D004926:Escherichia coli / Q000201:enzymology*; D008826:Microbial Sensitivity Tests; D009643:Norfloxacin / Q000031:analogs & derivatives* / Q000494:pharmacology; D009675:Novobiocin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D015366:Pefloxacin; D010957:Plasmids; D011804:Quinolines / Q000494:pharmacology*; D059004:Topoisomerase I Inhibitors; D059005:Topoisomerase II Inhibitors
chemical_list: D011804:Quinolines; D059004:Topoisomerase I Inhibitors; D059005:Topoisomerase II Inhibitors; D009675:Novobiocin; D015366:Pefloxacin; C006260:clorobiocin; D009643:Norfloxacin