Table 2.
Inhibitory activities of quinolones against DNA gyrase and topoisomerase IV
| Quinolone | IC50a for: |
IC50a for mutant topoisomerase IVb (fold increase over the IC50 for the wild type) | |
|---|---|---|---|
| DNA gyrase (wild type) | Topoisomerase IV (wild type) | ||
| Ciprofloxacin | >1,000 | 16.3 | 200 (12) |
| Garenoxacin | 25.9 | 11.1 | 117 (11) |
| Moxifloxacin | 32.4 | 11.6 | 126 (11) |
| Gatifloxacin | 21.0 | 7.95 | 96.3 (12) |
| Sparfloxacin | 589 | 11.6 | 109 (9.4) |
| Tosufloxacin | 400 | 43.5 | 601 (14) |
| Levofloxacin | 157 | 20.3 | 295 (15) |
| Norfloxacin | 757 | 37.6 | 344 (9.1) |
a
In micrograms per milliliter.
b
Mutant topoisomerase IV consisted of mutant ParC Gly81Cys and wild-type ParE.