title: Increased antibacterial activity of DW286, a novel fluoronaphthyridone antibiotic, against Staphylococcus aureus strains with defined mutations in DNA gyrase and topoisomerase IV.
abstract: To investigate the activity of DW286, a new fluoronaphthyridone, the quinolone resistance determining regions (QRDRs) of gyrA, gyrB, grlA and grlB genes in 64 Staphylococcus aureus clinical isolates were analyzed and the MICs of DW286 and comparator quinolones determined. Double and triple mutants in gyrA and grlA were resistant to ciprofloxacin, sparfloxacin, trovafloxacin and gemifloxacin but susceptible to DW286 (MIC 0.25-0.5 mg/l). The fourth alteration, Ser85Pro of GyrA was required to make a strain resistant to DW286 (MIC 4-32 mg/l). For a strain with the mutations at GyrA Ser84Leu and GrlA Ser80Phe, the MBC of DW286 was two-fold higher than its corresponding MIC, in contrast to ciprofloxacin which was not bactericidal.
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Hee-Jeong
authors.initials: HJ
authors.lastname: Yun
authors.forename: Yu-Hong
authors.initials: YH
authors.lastname: Min
authors.forename: Yeong Woo
authors.initials: YW
authors.lastname: Jo
authors.forename: Mi-Ja
authors.initials: MJ
authors.lastname: Shim
authors.forename: Eung-Chil
authors.initials: EC
authors.lastname: Choi
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D027081:DNA Gyrase / Q000235:genetics*; D027101:DNA Topoisomerase IV / Q000037:antagonists & inhibitors / Q000235:genetics*; D024881:Drug Resistance, Bacterial; D004791:Enzyme Inhibitors / Q000494:pharmacology; D024841:Fluoroquinolones / Q000494:pharmacology; D006801:Humans; D008826:Microbial Sensitivity Tests; D009287:Naphthyridines / Q000494:pharmacology*; D017354:Point Mutation; D013203:Staphylococcal Infections / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics; D059005:Topoisomerase II Inhibitors
chemical_list: C471029:7-(3-(aminomethyl)-4-(methoxyimino)-3-methyltetrahydro-1H-1-pyrrolyl)-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydro(1,8)naphthyridine-3-carboxylic acid; D000890:Anti-Infective Agents; D004791:Enzyme Inhibitors; D024841:Fluoroquinolones; D009287:Naphthyridines; D059005:Topoisomerase II Inhibitors; D027101:DNA Topoisomerase IV; D027081:DNA Gyrase