Ⅰa型牛源无乳链球菌LZQ07006分离株BibA基因片段的分子特征分析  

Molecular Characterization Analysis of BibA Gene in the Isolate LZQ07006 of SerotypeⅠa Streptococcus agalactiae from Bovine

作　　者：常瑞祥[1] 王旭荣[1] 王磊[1] 张景艳[1] 秦哲[1] 孔晓军[1] 王孝武[1] 李建喜[1] 杨志强[1] 王学智[1] 

机构地区：[1]中国农业科学院兰州畜牧与兽药研究所,甘肃省中兽药工程技术研究中心,甘肃兰州730050

出　　处：《中国畜牧兽医》2014年第5期34-38,共5页China Animal Husbandry & Veterinary Medicine

基　　金：国家奶牛产业技术体系科学家岗位项目(CARS37);甘肃省农业生物技术研究与应用开发项目(GNSW-2013-28);公益性行业(农业)科研专项(201303040-01)

摘　　要：试验旨在对Ia型牛源无乳链球菌BibA基因及其编码的蛋白进行分子特征分析，为进一步研究BibA蛋白的表达及免疫原性提供理论依据。采用PCR技术扩增牛源无乳链球菌LZQ07006分离株BibA基因片段，并将其克隆人pMD20T载体后测序，采用生物学软件对BibA基因及其推导的蛋白进行生物信息学分析。结果显示，LZQ07006菌株BibA基因片段长度为1185bp，未出现基因缺失，编码395个氨基酸，与GenBank中已发表的不同血清型的无乳链球菌核苷酸同源性和推导的氨基酸同源性分别为45．0％～99．8％和12．3％～99．5％；BibA基因片段是一个稳定的分泌性外膜蛋白，亲水性较好，存在1—32位氨基酸的信号肽，剪切位点在第3233位氨基酸之间的蛋白片段上。因此，牛源无乳链球菌BibA蛋白可作为奶牛乳房炎诊断和预防的应用性候选蛋白，但需深入研究。This study was aimed at analyzing the molecular characteristics of BibA gene and its expression protein, provi ding theoretical basis for the further study on the expression and immunogenicity of BibA protein. The BibA gene of the isolate LZQ07006 of serotype I a Streptococcus agalactiae from bovine was amplified using the PCR method, cloned into pMD20 T vector and then sequenced. The molecular characteristics of BibA gene and its expression protein were analyzed using a variety of biological software. The results showed that BibA gene of LZQ07006 was 1185 bp and did not appear the gene deletion, and encoded 395 amino acids. The nucleotide sequence homology of BibA gene derived from LZQ07006 was 45.0% to 99.8% and the amino acid homology was 12.3%~ to 99.5 % among the corresponding sequences from different serotypes Streptococcus aga- lactiae published in GenBank. The derived amino acid showed that the BibA protein was a stable outer membrane protein, which was secretion protein and hydrophilic highly. The polypeptide contained a signal peptide consisting of 32 amino acids, with cleavage site between 32th and 33th amino acids. In conclusion, it was necessary to study the BibA protein in bovine Streptococcus agalactiae for application in diagnosis or prevention of dairy cow mastitis.

关 键 词：I a型 无乳链球菌 BibA基因 克隆 序列分析 

分 类 号：S852.611[农业科学—基础兽医学]