Clerocidin, a terpenoid antibiotic, inhibits bacterial DNA gyrase.

DNA topoisomerases catalyze the topological interconversions of DNA molecules which are required for several essential processes in DNA metabolism including replication, recombination, transcription, and chromosome separation at mitosis1}.They are the target for the action of potent antitumor and antibacterial agents.A bacterial type II topoisomerase, bacterial gyrase, is the target of the quinolone antibacterial agents2'3).The effectiveness of the quinolones indicates that bacterial DNA gyrase is a target for clinically useful antibacterial agents.This has stimulated interest in searches for non-quinolone DNA gyrase inhibitors.These