TABLE 3.
Inhibitory activities for type II topoisomerases and antibacterial activities of gatifloxacin and the other quinolones
| Quinolone | MIC (μg/ml) against IID553 | IC50 (μg/ml) against:
|
IC50 ratioa | Target preference | |
|---|---|---|---|---|---|
| DNA gyrase | Topoisomerase IV | ||||
| Gatifloxacin | 0.25 | 25.9 | 7.27 | 3.56 | DNA gyrase |
| AM-1147 | 0.25 | 19.4 | 4.05 | 4.79 | DNA gyrase |
| AM-1121 | 0.5 | 181 | 11.7 | 15.5 | Topoisomerase IV |
| Ciprofloxacin | 0.5 | 138 | 6.85 | 20.1 | Topoisomerase IV |
| Clinafloxacin | 0.063 | 4.28 | 1.90 | 2.25 | DNA gyrase |
| Moxifloxacin | 0.25 | 21.8 | 6.04 | 3.61 | DNA gyrase |
| Sparfloxacin | 0.25 | 145 | 8.28 | 17.5 | DNA gyrase |
| Trovafloxacin | 0.125 | 17.7 | 3.07 | 5.77 | Topoisomerase IV |
| Levofloxacin | 1 | 89.3 | 15.9 | 5.62 | Topoisomerase IV |
| Norfloxacin | 4 | 582 | 35.2 | 16.5 | Topoisomerase IV |
a
IC50 ratio, IC50 against DNA gyrase/IC50 against topoisomerase IV.