Sequencing of Gyrase and Topoisomerase IV Quinolone-Resistance-Determining Regions of Chlamydia trachomatis and Characterization of Quinolone-Resistant Mutants Obtained In Vitro

• DOI: 10.1128/aac.42.10.2474
• Publication Date: 2018-10-09T00:29:31Z
• Authors: Sophie Dessus-Babus; Cécile M. Bébéar; Alain Charron; Christiane Bébéar; Bertille de Barbe...
• Keywords: Sparfloxacin; Quinolone; Topoisomerase IV

ABSTRACT The L2 reference strain of Chlamydia trachomatis was exposed to subinhibitory concentrations ofloxacin (0.5 μg/ml) and sparfloxacin (0.015 select fluoroquinolone-resistant mutants. In this study, two resistant strains were isolated after four rounds selection. C. mutants presented with high-level resistance various fluoroquinolones, particularly sparfloxacin, for which a 1,000-fold increase in the MICs mutant compared MIC susceptible found. unrelated antibiotics (doxycycline erythromycin) identical those strain. gyrase ( gyrA , gyrB ) topoisomerase IV parC parE genes partially sequenced. A point mutation found quinolone-resistance-determining region (QRDR) both strains, leading Ser83→Ile substitution Escherichia coli numbering) corresponding protein. QRDRs These results suggest that DNA is primary target sparfloxacin.