【摘要】 目的研究氟喹诺酮类药物对金黄色葡萄球菌norA基因表达的影响。方法荧光测定法研究氟喹诺酮类药物在临床分离的金黄色葡萄球菌SAUz及其诱导耐药菌中的蓄积量及能量抑制剂羰氰氯苯腙(CCCP)对蓄积量的影响,应用狭线杂交法检测细菌norA基因转录水平。结果氟喹诺酮类药物在诱导耐药菌SAUz-16中的蓄积量明显低于其亲代株SAUz,加入CCCP后,亲水性氟喹诺酮类药物在SAUz-16菌体中蓄积量增加,但仍未达到亲代株的稳态水平,诱导耐药菌SAUz-16 norA基因转录水平高于其亲代菌SAUz。结论氟喹诺酮类药物可导致norA基因表达增加,norA基因表达增加导致的氟喹诺酮类药物泵出增加是药物在金黄色葡萄球菌菌体内蓄积量减少的原因之一。更多还原

【Abstract】 OBJECTIVE To study the effect of fluoroquinolones on the level of transcription of norA gene in Staphylococcus aureus(SAU).METHODS The accumulation of fluoroquinolones in SAUz and its induced resistant strain(SAUz-16) and the effect of carbonyl cyanide m-chlorophenylhydrazone(CCCP) on accumulation were studied by fluorescence measured method.The level of transcription of norA gene was studied by slot blot hybridization.RESULTS The steady-state accumulation of SAUz-16 was lower than that of its parent(SAUz).The accumulation of hydrophilic fluoroquinolones in SAUz-16 increased obviously when CCCP was added,but it is lower than that of SAUz.The level of transcription of norA gene in SAUz-16 was higher than that of SAUz.CONCLUSIONS Fluoroquinolones can increase the level of transcription of norA gene.The increase in efflux of hydrophilic fluoroquinolones resulted from the increase in transcription of norA gene is one of causes of decrease in the accumulation of drugs in S.aureus.更多还原