牛分枝杆菌Ag85B的生物信息学分析及多表位候选抗原的构建  

Bioinformatics analysis of Mycobacterium bovis Ag85B and construction of a multi-epitope candidate antigen

作　　者：董希望 张岩 魏稚彤 李文欣 刘思宇 梁栋 赵海涛 DONG Xiwang;ZHANG Yan;WEI Zhitong;LI Wenxin;LIU Siyu;LIANG Dong;ZHAO Haitao(College of Animal Science and Technology,Henan Agricultural University,Zhengzhou 450002,China;Lushan County Animal Husbandry Technology Extension Station,Pingdingshan 467399,China)

机构地区：[1]河南农业大学动物科技学院,郑州450002 [2]河南省鲁山县畜牧技术推广站,河南平顶山467399

出　　处：《黑龙江畜牧兽医》2024年第15期62-65,72,118,119,共7页Heilongjiang Animal Science And veterinary Medicine

基　　金：国家自然科学基金青年基金项目(32202636);河南省重大科技专项“地方畜禽精准快育种体系构建与新品种选育”(221100110200)。

摘　　要：为了构建基于牛分枝杆菌Ag85B蛋白的多表位候选抗原,试验采用生物信息学方法对Ag85B蛋白的理化性质、亲/疏水性、二级结构等进行分析,预测其T、B淋巴细胞抗原表位,并构建以pET-28a(+)为载体的多表位候选抗原,分析预测多表位候选抗原的理化性质、抗原性并进行免疫模拟。结果表明:Ag85B蛋白有325个氨基酸残基,相对分子量为34.58085,理论等电点为5.62,脂肪系数为72.18,亚细胞定位于线粒体、细胞质和高尔基体中,具有亲水性、信号肽和跨膜结构域,属于分泌型蛋白,其无规则卷曲和β-转角结构的占比分别28.15%和8.62%,含有3个T淋巴细胞优势表位和8个B淋巴细胞优势表位。构建的Ag85B多表位候选抗原为亲水性蛋白和非致敏原,两次预测免疫原性参数分别为0.893和1.524,可诱导特异性的体液和细胞免疫应答。说明试验成功构建出基于牛分枝杆菌Ag85B蛋白的多表位候选抗原,且该多表位候选抗原可能诱导机体产生T、B淋巴细胞免疫应答。In order to construct a multi-epitope candidate antigen based on Mycobacterium bovis Ag85B protein,in the experiment,bioinformatics methods were used to analyze the physicochemical properties,hydrophilicity/hydrophobicity,and secondary structure of Ag85B protein,and to predict its antigenic epitopes for T and B lymphocytes.A multi-epitope candidate antigen was constructed into the vector pET-28a(+),and the physicochemical properties,antigenicity and immunosimulation of the multi-epitope candidate antigen were analyzed and predicted.The results showed that Ag85B protein had 325 amino acid residues,relative molecular weight of 34.58085,theoretical isoelectric point of 5.62,and fat coefficient of 72.18;it subcellularly localized in mitochondria,cytoplasm and Golgi,with hydrophilic,signal peptide and transmembrane structural domains;it belonged to the secretory protein;the percentages of irregularly curled andβ-turned structures were 28.15%and 8.62%,respectively,and it contained three T-lymphocyte dominant epitopes and eight B-lymphocyte dominant epitopes.The constructed multi-epitope candidate antigen of Ag85B was hydrophilic protein and non-allergen;the two predicted immunogenicity parameters were 0.893 and 1.524,respectively;it could induce specific humoral and cellular immune responses.The results indicated that the test successfully constructed a multi-epitope candidate antigen based on Mycobacterium bovis Ag85B protein,and the multi-epitope candidate antigen might induce T and B lymphocyte immune responses in the organism.

关 键 词：牛分枝杆菌 抗原表位 AG85B 生物信息学 多表位候选抗原 

分 类 号：S852.65[农业科学—基础兽医学]