能量抑制剂CCCP对环丙沙星在阴沟肠杆菌内聚积的影响

Effects of Energy Inhibitor Carbonyl Cyanaide m-Chlorophenylhydrazone (CCCP) on Accumulation of Ciprofloxacin in Enterobater Cloacae Clinical Isolates

目的:研究临床分离阴沟肠杆菌对环丙沙星的聚积以及能量抑制剂间苯腙氯羰氰(CCCP)对细菌摄取环丙沙星的影响,探讨主动泵出机制在细菌对喹诺酮耐药性产生中的作用。方法:应用荧光光度法测定阴沟肠杆菌细胞内环丙沙星的浓度,并对应用CCCP前后细菌细胞内环丙沙星聚积稳态浓度进行比较。结果:受试菌对环丙沙星的摄取均在5min内达到稳态浓度,耐药菌株的稳态浓度低于敏感菌株,应用CCCP后耐药菌细胞内的环丙沙星聚积浓度明显增加。结论:细菌细胞内能量依赖的环丙沙星聚积浓度的减少,在阴沟肠杆菌对环丙沙星产生的耐药性中具有一定作用。

Objective： To investigate the effects of clinical isolates of Enterobacter Cloacae on accumulation of ciprofloxacin and the effects of carbonyl cyanide m-chlorophenylhydrazone（CCCP） on uptake of ciprofloxacin in E.cloacae isolates. To explore the effects of initiative pump mechanism on drug resistance of quinolones. Methods： The accumulation of ciprofloxacin was determined by using a modification of fluorometric assay, and the intracellular concentration of ciprofloxacin was compared before and after the use of CCCP. Results： The accumulation of ciprofloxacin for all detected isolates of E.cloacae reached to a stable concentration within 5 min, and the intracellular stable concentration of ciprofloxacin was lower in quinolone-resistant isolates than that in quinolone-susceptible isolates. The accumulation of ciprofloxacin in resistant isolates increased after incubated with CCCP. Conclusion： Energy-dependent active efflux may play a certain role in ciprofloxacin resistance in E. cloacae by decreasing the accumulation of ciprofloxacin.