摘要
为了探讨非结核分枝杆菌中EsxB蛋白的生物学功能,试验以实验室分离的母牛分枝杆菌、新金分枝杆菌和耻垢分枝杆菌为对象,克隆了esxB基因,应用生物信息学方法进行系统发生分析,对EsxB蛋白进行生物学特性、保守区分析以及抗原表位、可能的三级结构预测。结果表明:克隆的3种非结核分枝杆菌的esxB基因大小分别为309 bp、303 bp、294 bp,推导的氨基酸序列与Gen Bank中登录的相应菌种的氨基酸序列同源性分别为95%或97%、100%、100%;属于WXG100蛋白超家族中CFP-10亚家族成员,具有该亚家族保守的α-螺旋和Yxxx D/E序列;预测到3条肽链线性B细胞表位各1个,T细胞表位各4个、9个、5个,部分T细胞表位与结核杆菌CFP10的CD8+T细胞表位有5~6个共同氨基酸。
To explore the biological function of EsxB protein in nontuberculosis mycobacteria, esxB genes were cloned using Mycobacterium vaccae, Mycobacteriu neoaurum and Mycobacterium smegmatis isolated from laboratory as subjects. Phylogenetic analysis was performed using bioin- formatics methods, and then the biological characteristics, conservative region, antigen epitopes and possible tertiary structure of EsxB protein were analyzed and predicted, respectively. The results showed that the sizes of esxB genes cloned from three species of nontubereulosis mycobacteria were 309 bp, 303 bp and 294 bp, respectively. The deduced amino acid sequence shared 95% or 97%, 100%, and 100% homology with that of corresponding strains registered in GenBank, respectively. The EsxB protein belonged to one of CFP - 10 subfamily of WXG100 protein superfamily, and had the conservative alpha helices and YxxxD/E sequence of subfamily. It was predicted that there were one of three linear B cell epitopes with 4, 9, and 5 T cell epitopes in each peptide, respectively. The part of the T cell epitopes had five to six common ami- no acids with CD8^＋ T cell epitopes of Mycobacterium tuberculosis CFPIO.
出处
《黑龙江畜牧兽医》
CAS
北大核心
2017年第3期19-23,289,290,共7页
Heilongjiang Animal Science And veterinary Medicine
基金
国家自然科学基金项目(31272566)
吉林省科技发展计划项目(20140204069NY)
