title: In vitro activity of DNA gyrase inhibitors, singly and in combination, against Mycobacterium avium complex.
abstract: 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.
authors.affiliation: Department of Internal Medicine, Ohio State University College of Medicine, Columbus.
authors.forename: T J
authors.initials: TJ
authors.lastname: Babinchak
authors.forename: R J
authors.initials: RJ
authors.lastname: Fass
mesh_terms: 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
chemical_list: D049933:Aminocoumarins; D003374:Coumarins; D004791:Enzyme Inhibitors; D059005:Topoisomerase II Inhibitors; D009675:Novobiocin; D002939:Ciprofloxacin; C004628:coumermycin