辽宁地区猪源大肠埃希菌喹诺酮类耐药基因的检测与分析  

Detection and Analysis of Quinolone Resistance Genes in Swine Escherichia coli from Liaoning Area

作　　者：赵凤菊[1] 关淼[1] 李清竹[1] 顾贵波[1] 

机构地区：[1]辽宁省动物疫病预防控制中心,辽宁沈阳110164

出　　处：《河南农业科学》2017年第12期126-129,共4页Journal of Henan Agricultural Sciences

基　　金：辽宁省自然科学基金项目(201402573)

摘　　要：为了解辽宁地区猪源大肠埃希菌中质粒介导的喹诺酮类耐药基因(PMQR)的分布及DNA解旋酶基因(gyrA、gyrB)和拓扑异构酶Ⅳ基因(parC、parE)等编码的喹诺酮耐药决定区突变特征,以及这些基因突变对喹诺酮类抗生素耐药性的影响,采用PCR方法对23株喹诺酮类耐药菌株进行gyrA、gyrB、parC、parE、aac(6')-Ib-cr、qep A、qnrA、qnrB、qnrC、qnrD、qnrS等11个基因的检测与序列分析,并分析其耐药谱。结果表明,23株喹诺酮类耐药菌株耐药谱广,均对萘啶酸耐药;PMQR基因的阳性率为86.96%(20/23),其中5株携带3种PMQR基因,9株携带2种PMQR基因,6株携带1种PMQR基因,aac(6')-Ib-cr的阳性率最高,qep A、qnrB、qnrC和qnrS阳性率次之,qnrA、qnrD基因未被检测到;在对15株耐药菌株gyr基因和par基因编码的喹诺酮类耐药决定区的突变分析中发现,K447E的突变率最高,其次为D87N、D426N、S80I和A56T。由此可见,在辽宁地区PMQR基因及靶位突变成为猪源大肠埃希菌对喹诺酮类药物产生耐药性的重要原因。To investigate master distribution of plasmid-mediated quinolone resistance genes( PMQR),quinolone resistant determining regions( QRDRs) mutation characteristics of DNA helicase genes( gyrA,gyrB) and topoisomerase Ⅳ genes( parC,parE) and their effects on the bacterial resistance to the quinolone antibiotics of Escherichia coli fromLiaoning area. gyrA,gyrB,parC,parE,aac( 6')-Ib-cr,qep A,qnrA,qnrB,qnrC,qnrD and qnrS genes of 23 quinolone resistant strains isolated were detected by PCR.The results showed that positive rate of PMQR gene was 86. 96%( 20/23),in addition 5 isolates harbored three kinds of PMQR genes,9 isolates harbored two kinds of PMQR genes and 6 isolates harbored one kinds of PMQR genes. Positive rate of aac( 6')-Ib-cr gene was the highest,followed by qep A,qnrB,qnrC and qnrS genes,none of qnrA and qnrD genes was detected; Analysis of gyrand pargenes QRDRs mutation among 15 resistant strains were isolated,mutation rate of K447 E was the highest,followed by D87 N,D426 N,S80 I and A56 T. Therefore,PMQR genes and chromosome mediated target mutation is important cause of resistance to quinolones for Escherichia coli from swine in Liaoning area.

关 键 词：猪源大肠埃希菌 喹诺酮类耐药基因 PCR 序列分析 辽宁 

分 类 号：S855.1[农业科学—临床兽医学]