肠出血性大肠杆菌O157毒力及黏附相关基因的PCR检测和PCR-RFLP分析  

Detection of enterohaemorrhagic Escherichia coli O157 virulence and adherence associated genes and PCR-RFLP analysis

作　　者：丁红雷[1,2,3] 毛旭虎[1] 王豪举[2] 邹全明[1] 

机构地区：[1]第三军医大学临床微生物学及免疫学教研室重庆市生物制药工程技术研究中心,重庆400038 [2]西南大学动物科技学院重庆市牧草与草食家畜重点实验室,重庆400716 [3]西南大学蚕学与系统生物学研究所,重庆400715

出　　处：《中国兽医学报》2009年第3期308-311,共4页Chinese Journal of Veterinary Science

基　　金：军队杰出人才基金资助项目(04J009)

摘　　要：为了了解大肠杆菌O157分离菌株携带毒力及黏附相关基因的情况及菌株的多态性。用聚合酶链式反应扩增stx1、stx2、eaeA、ehxA、EspA和Tccp基因。选用限制性内切酶HincⅡ和EcoRⅡ对分离的O157∶H7菌株eaeA基因进行酶切,选用限制性内切酶HaeⅢ、HinfⅠ、EcoRⅡ和RsaⅠ对分离的O157∶H7菌株ehxA基因进行酶切,最后对这两个基因进行PCR-RFLP分析。结果,所有O157∶H7菌株扩增出eaeA、ehxA、EspA和Tccp基因,但没有扩增出stx1和stx2基因;4株O157∶H?菌株,均没有扩增出stx2、eaeA、ehxA、EspA和Tccp基因,且只有1株扩增出stx1基因。所有分离菌株的eaeA基因和ehxA基因选用限制性内切酶酶切之后所得酶切片段数目和大小与标准菌株的eaeA基因和ehxA基因选用限制性内切酶酶切之后所得酶切片段数目和大小相同。结果表明,由于所有菌株缺失stx2基因,其致病力相对较低,且在基因水平较为保守,多态性较为单一。To acquire the data of virulence and adherence associated genes and polymorphism of Escherichia coli O157 ： H7 isolates. Methods E. coli O157 isolates were examined by polymerase chain reaction （PCR） assay to determine the presence of stx1,stx2,eaeA,ehxA,EspA and Tccp. All eaeA genes of O157 ： H7 isolates were digested by restriction enzymes Hinc Ⅱ and EcoR Ⅱ and all etxA genes were digested by restriction enzymes HaeⅢ , Hinf Ⅰ , EcoRⅡand Rsa Ⅰ. Then,eaeA and ehxA were analysed by PCR RFLP. Result All O157 ： H7 isolates had eaeA, ehxA,EspA and Tccp genes,but had not stxl and stx2. All O157 ： H？ isolates had not stx2,eaeA,ehxA,EspA and Tccp genes,and All O157 ： H？ isolates had not stx1 except for one O157 ： H？. When eaeA and ehxA presented in isolates were digested by restriction enzymes,the numbers and sizes of the segments was equal to the numbers and si zes of the segments from standard strains whose eaeA and ehxA were digested by restriction enzymes,too. Conclu sion All O157 isolates lack of stx2 ,so they had a low virulence relatively,and they were conservative genetically,and the polymorphism is single.

关 键 词：大肠杆菌O157 毒力及黏附相关基因 PCR RFLP 

分 类 号：S852.61[农业科学—基础兽医学]