Sequencing of gyrase and topoisomerase IV quinolone-resistance-determining regions of Chlamydia trachomatis and characterization of quinolone-resistant mutants obtained In vitro.

ABSTRACT: The L2 reference strain of Chlamydia trachomatis was exposed to subinhibitory concentrations of ofloxacin (0.5 microg/ml) and sparfloxacin (0.015 microg/ml) to select fluoroquinolone-resistant mutants. In this study, two resistant strains were isolated after four rounds of selection. The C. trachomatis mutants presented with high-level resistance to various fluoroquinolones, particularly to sparfloxacin, for which a 1,000-fold increase in the MICs for the mutant strains compared to the MIC for the susceptible strain was found. The MICs of unrelated antibiotics (doxycycline and erythromycin) for the mutant strains were identical to those for the reference strain. The gyrase (gyrA, gyrB) and topoisomerase IV (parC, parE) genes of the susceptible and resistant strains of C. trachomatis were p

SUBMITTER: Dessus-Babus S 

PROVIDER: S-EPMC105861 | biostudies-literature | 1998 Oct

REPOSITORIES: biostudies-literature