TABLE 1.

Drug sensitivities of S. aureus and E. coli topoisomerasesa

TopoisomeraseIC50 (μM) of topoisomerase
SD8Ciprofloxacin
S. aureus gyrase1.45 ± 0.3548 ± 9
E. coli gyrase0.41 ± 0.032.35 ± 0.55
S. aureus Topo IV14.5 ± 0.58.4 ± 0.1
E. coli Topo IV270 ± 1034 ± 1
  • a The drug sensitivities of gyrases and Topo IVs were measured in the supercoiling and decatenation assays, respectively. Each assay was repeated two or three times, and the IC50s were determined based on the amounts of either the supercoiled DNA or decatenated DNA. Representative results are shown in Fig. 2 and 4.