Inhibition of DNA gyrase by optically active ofloxacin

Antimicrob Agents Chemother. 1987 Feb;31(2):325-7. doi: 10.1128/AAC.31.2.325.


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.

Publication types

  • Comparative Study

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Ciprofloxacin / pharmacology
  • Electrophoresis, Agar Gel
  • Escherichia coli / enzymology
  • Micrococcus / enzymology
  • Norfloxacin / pharmacology
  • Ofloxacin
  • Oxazines / pharmacology*
  • Topoisomerase II Inhibitors*


  • Anti-Bacterial Agents
  • Oxazines
  • Topoisomerase II Inhibitors
  • Ciprofloxacin
  • Ofloxacin
  • Norfloxacin