福氏志贺菌主动外排基因acrB的克隆与序列分析  

Cloning and sequence analysis of activite efflux gene acrB of Shigella flexneri 2a

作　　者：王松泰[1,2] 张继瑜[2] 魏小娟[2] 付元芳[1] 曹小安[3] 邱昌庆[3] 

机构地区：[1]甘肃农业大学动物医学院,甘肃兰州730070 [2]中国农业科学院兰州畜牧与兽药研究所,新兽药重点实验室,甘肃兰州730050 [3]中国农业科学院兰州兽医研究所,家畜疫病病原生物学国家重点实验室,甘肃兰州730046

出　　处：《甘肃农业大学学报》2008年第6期6-8,24,共4页Journal of Gansu Agricultural University

基　　金：国家自然科学基金项目(30671582)

摘　　要：以福氏志贺菌2a型菌株基因组为模板，经PCR扩增得acrB基因，将该基因克隆到pMD18-T Vector载体，将重组质粒进行PCR和酶切鉴定及序列测定．结果表明：测定序列与Genbank收录的福氏志贺菌参考序列同源性为99．7％，与大肠杆菌的acrB基因序列比较分析，序列同源性在98％～99％之间，说明志贺菌主动外排基因acrB在碱基序列和编码的氨基酸序列上均与大肠杆菌有很高的同源性，它可能是志贺菌引起多重耐药的主要原因．To identify the sequence of the active efflux gene acrB in Shigella flexneri 2a and analyze its sequence,the whole acrB gene was amplified by PCR from Shigella flexneri 2a genome DNA. The acrB gene was ligated with pMD18-T vector and transformed into competent cell DH5. Identification of recombinant vector was conducted by PCR and restriction enzyme digestion. Sequence analysis indicated that the sequence of acrB gene of Shigella flexneri 2a shared 99.8 % homology with the reference sequence of Shigella flexneri（Genebank No. NC_004337） and shared 98 %-99 % homo ison with E. coli. The active efflux gene aerB of Shigella flexneri 2a showed ding amino acids with E. coli and it was possible that Shigella flexneri was ICS. logy high were detected in comparhomology in bases,encoresistant to multiple antibiotics.

关 键 词：志贺菌 acrB基因 克隆 序列分析 

分 类 号：S852.612[农业科学—基础兽医学] Q786[农业科学—兽医学]