title: Inhibition of DNA gyrase by optically active ofloxacin.
abstract: Inhibition of DNA gyrase activity by optically active ofloxacins was studied and compared with the inhibition of norfloxacin and ciprofloxacin. The (-)-isomer of ofloxacin inhibited the supercoiling activity of gyrase from Micrococcus luteus more effectively than did the (+)-isomer. The 50% inhibitory concentrations of (-)-, (+/-)-, and (+)-ofloxacin; norfloxacin; and ciprofloxacin for gyrase from Escherichia coli were 0.78, 0.98, 7.24, 0.78, and 1.15 microgram/ml, respectively. These values correlated well with the antibacterial activity of each compound against intact bacterial cells.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002939:Ciprofloxacin / Q000494:pharmacology; D004587:Electrophoresis, Agar Gel; D004926:Escherichia coli / Q000201:enzymology; D008837:Micrococcus / Q000201:enzymology; D009643:Norfloxacin / Q000494:pharmacology; D015242:Ofloxacin; D010078:Oxazines / Q000494:pharmacology*; D059005:Topoisomerase II Inhibitors
chemical_list: D000900:Anti-Bacterial Agents; D010078:Oxazines; D059005:Topoisomerase II Inhibitors; D002939:Ciprofloxacin; D015242:Ofloxacin; D009643:Norfloxacin