Zweerink M M, Edison A
Antimicrob Agents Chemother. 1986 Apr;29(4):598-601. doi: 10.1128/AAC.29.4.598.
The ability of norfloxacin, amifloxacin, cinoxacin, ciprofloxacin, flumequine, nalidixic acid, ofloxacin (OFL), oxolinic acid, perfloxacin, pipemidic acid, and rosoxacin to inhibit the in vitro supercoiling activity of Micrococcus luteus DNA gyrase was compared with the ability of each drug to inhibit the growth of the M. luteus strain from which the gyrase was purified. The potency of the quinolones as DNA gyrase inhibitors did not always correlate with antimicrobial potency. For example, OFL was a less potent inhibitor of gyrase than rosoxacin, yet the MIC of OFL was 16-fold lower than that of rosoxacin. Similarly, the MICs of norfloxacin and ciprofloxacin (the most potent of the antibiotics tested in these assays) were several hundredfold lower than the MIC of nalidixic acid (the least potent of these antibiotics), but the inhibition of purified gyrase by these two quinolones was only 8- to 16-fold lower than that of nalidixic acid. These results suggest that factors in addition to inhibition of gyrase supercoiling activity are important in determining the potency of these drugs. Further studies indicated that the uptake of norfloxacin, OFL, and amifloxacin by M. luteus cells may not account for the large differences in MICs observed for these drugs (MICs of 0.8, 2.0, and 128 micrograms/ml, respectively).
将诺氟沙星、阿米氟沙星、西诺沙星、环丙沙星、氟甲喹、萘啶酸、氧氟沙星（OFL）、恶喹酸、培氟沙星、吡哌酸和咯索沙星抑制藤黄微球菌DNA促旋酶体外超螺旋活性的能力，与每种药物抑制从中纯化出促旋酶的藤黄微球菌菌株生长的能力进行了比较。喹诺酮类作为DNA促旋酶抑制剂的效力并不总是与抗菌效力相关。例如，OFL作为促旋酶抑制剂的效力低于咯索沙星，但其MIC比咯索沙星低16倍。同样，诺氟沙星和环丙沙星（这些试验中测试的最有效的抗生素）的MIC比萘啶酸（这些抗生素中效力最低的）的MIC低数百倍，但这两种喹诺酮类对纯化促旋酶的抑制作用仅比萘啶酸低8至16倍。这些结果表明，除了抑制促旋酶超螺旋活性外，其他因素在决定这些药物的效力方面也很重要。进一步的研究表明，藤黄微球菌细胞对诺氟沙星、OFL和阿米氟沙星的摄取可能无法解释这些药物观察到的MIC的巨大差异（MIC分别为0.8、2.0和128微克/毫升）。
