title: Relative beta-lactamase- and transpeptidase-inhibitory activities of the new quinolone WIN-57273 in Staphylococcus aureus.
abstract: The new quinolone WIN-57273 was shown to inhibit Staphylococcus aureus beta-lactamase activity noncompetitively in vitro with an apparent Ki value of 0.5 mM. MICs of penicillin G for a highly quinolone-resistant, beta-lactamase-negative strain in the presence of exogenous beta-lactamase decreased considerably when subinhibitory concentrations of WIN-57273 were added. Furthermore, the attachment transpeptidase reaction, investigated on whole cells of S. aureus, was impeded by WIN-57273 concentrations of greater than or equal to 30 microM. While these interactions suggest a novel mechanism of action for this compound, they are probably not relevant to the overall antibacterial potency of WIN-57273.
authors.affiliation: Département de Microbiologie Médicale, Centre Médical Universitaire, Geneva, Switzerland.
authors.forename: Y X
authors.initials: YX
authors.lastname: Furet
authors.forename: C
authors.initials: C
authors.lastname: Lucain
authors.forename: J C
authors.initials: JC
authors.lastname: Pechère
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D024841:Fluoroquinolones; D008826:Microbial Sensitivity Tests; D010458:Peptidyl Transferases / Q000037:antagonists & inhibitors*; D015363:Quinolones / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects*; D065093:beta-Lactamase Inhibitors
chemical_list: D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D015363:Quinolones; D065093:beta-Lactamase Inhibitors; C062556:Win 57273; D010458:Peptidyl Transferases