志贺菌主动外排泵acrAB-tolC及调控基因marOR突变与耐药的关系  

Relation of acrAB-tolC efflux pump and marOR regulated gene mutation with antimicrobial resistance in Shigella

作　　者：任静朝[1] 段广才[1] 宋春花[1] 吕锐利[1] 张卫东[1] 郗园林[1] 

机构地区：[1]郑州大学公共卫生学院流行病学与卫生统计学教研室,河南郑州450001

出　　处：《吉林大学学报（医学版）》2010年第1期45-48,共4页Journal of Jilin University：Medicine Edition

基　　金：河南省科技厅科技攻关项目资助课题(0424410035)

摘　　要：目的:研究志贺菌的耐药状况,检测临床分离志贺菌主动外排泵acrAB-tolC基因及调控基因marOR的突变情况,并探讨其与耐药性的关系。方法:对159株临床分离的志贺菌进行四环素、氯霉素、氨苄青霉素、庆大霉素、诺氟沙星、复方新诺明6种药物的药敏试验和有机溶剂耐受试验,对其acrAB-tolC基因和marOR基因进行聚合酶链反应(PCR)扩增,并进行限制性内切酶酶切与单链构象多态性(SSCP)分析。结果:159株临床分离的志贺菌属细菌筛选出4株敏感株、18株耐单药株和137株耐多药株,耐多药率为86.2%(137/159);159株中有122株对有机溶剂耐受,耐受率为76.7%(122/159);159株均扩增出acrAB-tolC基因和marOR基因,未发现基因缺失株;单链构象多态性分析,155株耐药菌株中,marOR基因的突变率为17.4%,acrA基因的突变率为5.8%,acrB基因的突变率为3.9%,tolC基因的突变率为2.6%;4株敏感株未发现marOR、acrA、acrB和tolC基因突变。结论:临床分离的志贺菌耐多药率和有机溶剂耐受率均较高,且存在较高的marOR基因突变率。Objective To identify the antimicrobial resistance and the mutations in acrAB-tolC efflux pump and marOR regulated genes in Shigella, then analyze their relations. Methods One hundred and fifty-nine clinical isolates of Shigella were collected. Susceptibility tests of tetracycline （ TE）, chloramphenicol （C）, ampicillin （Am）, gentamycin （GM）, norfloxacin （NOR） and selectrin （SMZ-TMP） and organic-solvent tolerance test were performed in all isolates. The acrA, acrB, tolC and marOR genes of these isolates were amplified by polymerase chain reaction （PCR） respectively. The PCR products were digested by restriction endonuclease Taq Ⅰ or Hinf Ⅰ , then analyzed by single strand conformation polymorphism （SSCP）. Results In 159 clinical isolates, 137 multi-drug strains and 4 sensitive strains were discovered. The rate of multi-drug resistance was 86.2%. 122 strains were organic-solvent tolerance and the rate of organic-solvent tolerance was 76.7 %. The marOR and acrAB tolC genes were found in all strains and the lack of the four genes were not found. SSCP analysis revealed that the rates of mutations in marOR, acrA, acrB and tolC genes were 17.4%, 5.8%, 3.9%, and 2.6%, respectively. Conclusion The Shigella spp. has high multi-drug resistance rate and organic-solvent tolerance rate, and the mutation rate of marOR gene is high too.

关 键 词：志贺菌 acrAB-tolC主动外泵基因 marOR基因 耐多药 

分 类 号：R378.25[医药卫生—病原生物学]