In vitro activity of DNA gyrase inhibitors, singly and in combination, against Mycobacterium avium complex.
The in vitro activities of the DNA gyrase inhibitors ciprofloxacin, coumermycin, and novobiocin against 31 clinical isolates of Mycobacterium avium complex were studied using a microdilution technique. Minimal inhibitory concentrations (MICs) were determined in 4 days using Middlebrook 7H9 broth, and minimal bactericidal concentrations (MBCs) were determined by subculturing to Middlebrook 7H10 agar. MICs were: ciprofloxacin, 0.5-greater than 16 (mean, 4.1) micrograms/ml; novobiocin, 4-greater than 128 (mean, 54.7) micrograms/ml; and coumermycin, 2-greater than 16 (mean, 17.5) micrograms/ml. MBCs were usually more than two dilution steps higher than MICs. Checkerboard studies failed to reveal synergistic or antagonistic inhibitory activity of DNA gyrase-A and DNA gyrase-B inhibitors in vitro.
Babinchak
T J
TJ
Department of Internal Medicine, Ohio State University College of Medicine, Columbus.
Fass
R J
RJ
D049933:Aminocoumarins; D002939:Ciprofloxacin / Q000494:pharmacology*; D003374:Coumarins / Q000494:pharmacology; D004357:Drug Synergism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D015269:Mycobacterium avium Complex / Q000187:drug effects* / Q000254:growth & development; D009675:Novobiocin / Q000494:pharmacology*; D059005:Topoisomerase II Inhibitors
D049933:Aminocoumarins; D003374:Coumarins; D004791:Enzyme Inhibitors; D059005:Topoisomerase II Inhibitors; D009675:Novobiocin; D002939:Ciprofloxacin; C004628:coumermycin