Inhibitory activities of quinolones against DNA gyrase of Chlamydia pneumoniae

Abstract

The gyrA and gyrB genes of Chlamydia pneumoniae TW-183 were cloned, and their proteins were purified by use of a fusion system with a maltose-binding protein. The 50% inhibitory concentrations of garenoxacin, sparfloxacin, moxifloxacin, gatifloxacin, and levofloxacin were 10.1, 47.5, 39.6, 64.2, and 156.9 microg/ml, respectively, and the MICs against C. pneumoniae TW-183 were 0.008, 0.016, 0.063, 0.125, and 0.25 microg/ml, respectively.

FIG. 1.

Enzymatic activities of purified recombinant DNA gyrase of C. pneumoniae TW-183. Lane 1, GyrA-MBP (4 U) and GyrB-MBP (4 U) without ATP; lane 2, GyrA-MBP (4 U) and GyrB-MBP (4 U) without Mg²⁺; lane 3, GyrA-MBP (8 U) and GyrB-MBP (8 U); lane 4, GyrA-MBP (4 U) and GyrB-MBP (4 U); lane 5, GyrA-MBP (8 U) and GyrB-MBP (3/2 U); lane 6, GyrA-MBP (3/2 U) and GyrB-MBP (8 U); lane 7, GyrA-MBP (2 U) and GyrB-MBP (2 U); lane 8, GyrA-MBP (1 U) and GyrB-MBP (1 U).

FIG. 2.

DNA-supercoiling activity of gyrase in the presence of garenoxacin and levofloxacin.