FIG. 3.

Site specificity of quinolone-promoted DNA cleavage by S. pneumoniae DNA gyrase. EcoRI-cut pBR322 DNA (0.4 μg) was incubated with GyrA (0.45 μg) and GyrB (1.7 μg) in the absence or presence of quinolones at the indicated concentrations (in micromolar). After treatment with SDS and proteinase K, DNA samples were examined by electrophoresis in 1% agarose. Lanes M, b, and a; DNA size markers, linear pBR322, and supercoiled pBR322, respectively. GEMI, gemifloxacin; GATI, gatifloxacin; MOXI, moxifloxacin; CIP, ciprofloxacin.