多重耐药铜绿假单胞菌MexAB-OprM的表达及mexR基因的突变  

Expression of MexAB-OprM and mutation of mexR in multi-drug resistant Pseudomonas aeruginosa*

作　　者：吴祥林 肖丽霞[2] 马东礼[2] 管有理 刘青 

机构地区：[1]深圳市光明新区人民医院检验科,广东深圳518106 [2]深圳市儿童医院检验科,广东深圳518026

出　　处：《国际检验医学杂志》2013年第3期288-290,共3页International Journal of Laboratory Medicine

基　　金：深圳市科研项目(201103209)

摘　　要：目的分析MexAB-OprM主动外排系统在铜绿假单胞菌耐药性中的作用,并讨论MexAB-OprM高表达与mexR基因突变的关系。方法 L-酚丙氨基-L-氨基酰-β-萘胺(MC207,110)联合环丙沙星(CIP)筛选13株多重耐药铜绿假单胞菌主动外排系统表型;RT-PCR检测13株多重耐药和7株全敏感的铜绿假单胞菌结构基因mexB的mRNA相对含量,推测MexAB-OprM表达水平;对6株MexAB-OprM高表达的多重耐药铜绿假单胞菌进行mexR基因扩增、测序和比对。结果 13株多重耐药铜绿假单胞菌9株主动外排系统表型阳性,阳性率69.2%;所有检测株中均有MexAB-OprM表达,其中有6株多重耐药株高表达;6株多重耐药高表达株中有5株存在mexR基因的突变。结论 MexAB-OprM主动外排系统高表达是导致本院铜绿假单胞菌多重耐药的重要原因,而mexR基因的突变又是导致MexAB-OprM高表达的主要原因。Objective To analyze the effect of active efflux system MexAB-OprM in the multi--drug resistance of Pseudomonas aeruginosa（PA）, and to study the relationship between expression of MexAB-OprM and mutation of mexR. Methods The active efflux phenotype in the 13 strains of multi--drug resistant PA were screened by efflux inhibitors MC207,110. The levels of mexR mRNA of 13 MDR strains and 7 standard susceptible strains were determined by real time PCR. The mexR gene in 6 strains of high level MexAB-OprM was amplified and the gene sequence were analyzed. Results The active efflux phenotype was identified in 9 strains. MexAB-OprM was over expressed in 6 strains, in which there were 5 strains carrying mexR gene mutation. Conclusion The high level expression of MexAB-OprM active efflux system played an important role in PA multi--drug resistance. The muta tion of mexR might be the main reason for the over expression of MexAB-OprM.

关 键 词：假单胞菌 铜绿 抗药性 多药 外排系统 MEXAB-OPRM mexR 

分 类 号：R440[医药卫生—诊断学]