应用生物信息学分析结核分枝杆菌表位串联蛋白W541的结构和功能  

Bioinformatic analysis of the structure and function of Mycobacterium tuberculosis epitope-tandem protein W541

作　　者：李鹏川 梁艳 张林西[1] 吴雪琼 Li Pengchuan;Liang Yan;Zhang Linxi;Wu Xueqiong(Basic Medical College of Hebei North University,Zhangjiakou 075000,China;Key Laboratory of Tuberculosis Prevention and Control,Beijing Key Laboratory of Tuberculosis Diagnosis and Treatment,Institute of Tuberculosis Research,the Eighth Medical Center of the PLA General Hospital,Beijing 100091,China)

机构地区：[1]河北北方学院基础医学院,张家口075000 [2]中国人民解放军总医院第八医学中心全军结核病研究所全军结核病防治重点实验室结核病诊疗新技术北京市重点实验室,北京100091

出　　处：《中国防痨杂志》2022年第12期1345-1357,共13页Chinese Journal of Antituberculosis

基　　金：医学创新工程专项重点项目(18CXZ028);国家重大传染病专项(2018ZX10731-301-005)。

摘　　要：目的:应用生物信息学方法预测分析结核分枝杆菌表位串联蛋白W541的结构和功能。方法:本实验室构建的新型结核分枝杆菌DNA疫苗编码蛋白W541是由增殖期抗原Ag85A、Ag85B和潜伏相关抗原Rv3407、Rv1733c的表位串联起来的,其氨基酸序列分别利用ProtParam、Protscale、TMHMM、SOPMA、SWISS-MODEL、PSORT、SignalP、NetNGlyc、NetPhos、SYFPEITHI、RANKPEP、IEDB、NetMHC、STRING和EXPASY生物信息学软件分析该蛋白质的理化性质、亲(疏)水性、跨膜螺旋、二级和三级结构、亚细胞定位、信号肽及糖基化、磷酸化位点,B细胞、辅助性T(Th)细胞和细胞毒性T淋巴细胞(CTL)表位,以及蛋白相互作用网络及与人类蛋白的同源性。结果:W541蛋白共由704个氨基酸构成,分子式为C_(3329)H_(5035)N_(923)O_(993)S_(24),不稳定指数为45.37,为亲水性不稳定蛋白。无跨膜螺旋区及信号肽,细胞内定位为膜蛋白;其二级结构中α-螺旋、β-折叠、β-转角、无规则卷曲分别占比为26.99%、19.03%、11.51%、42.47%;有6个糖基化位点。62个磷酸化位点,其中苏氨酸、丝氨酸和酪氨酸磷酸化位点分别为15个、35个和12个;具有T细胞和B细胞优势表位;W541蛋白与10个蛋白有相互作用;该蛋白的氨基酸序列与人蛋白的同源性为3.27%。结论:结核分枝杆菌表位串联蛋白W541存在多个潜在的B细胞及T细胞抗原表位,其中以T细胞抗原表位占优势,可能具有较好的免疫原性,并发挥重要的调控作用,为进一步动物实验评价奠定了基础。Objective:To predict and analyze the structure and function of Mycobacterium tuberculosis(MTB)epitope-tandem protein W541 by bioinformatics method.Methods:W541 protein constructed in our laboratory was encoded by a novel multi-antigen epitope-tandem DNA vaccine composed of the epitopes of MTB proliferative antigens Ag85A,Ag85B,latent-related antigens Rv3407 and Rv1733c.Its amino acid sequence of physicochemical properties,hydrophilic(hydrophobic),transmembrane helix,secondary and tertiary structures,subcellular localization,signal peptide,glycosylation and phosphorylation sites,B cell,helper T(Th)and cytotoxic T lymphocyte(CTL)epitopes,the protein interaction network,the homology between W541 protein and human protein was analyzed using bioinformatics softwares ProtParam,Protscale,TMHMM,SOPMA,SWISS-MODEL,PSORT,SignalP,NetNGlyc,NetPhos,SYFPEITHI,RANKPEP,IEDB,NetMHC,STRING,and EXPASY,respectively.Results:W541 protein was composed of 704 amino acids,with the molecular formula of C_(3329)H_(5035)N_(923)O_(993)S_(24),the instability index of 45.37,which was hydrophilic unstable protein.The proportions ofα-helix,β-fold,β-corner and irregular crimp in its secondary structure were 26.99%,19.03%,11.51%and 42.47%,respectively.It had no transmembrane helix region or signal peptides,which was an intracellular membrane protein.W541 protein had 6 glycosylation sites,and 62 phosphorylation sites,including 15 threonine,35 serine and 12 tyrosine phosphorylation sites,respectively.W541 protein had multiple potential T cell and B cell epitopes.W541 protein interacted with 10 proteins.The amino acid sequence of W541 protein had less than 3.27%homology with the human protein.Conclusion:MTB epitope-tandem protein W541 has multiple potential T-cell and B-cell epitopes.Among them,T-cell epitopes were dominant,which may have better immunogenicity,play an important regulatory role and lay a foundation for further animal experimental evaluation.

关 键 词：免疫 分枝杆菌 结核 抗原 模型 结构 

分 类 号：R52[医药卫生—内科学] S852.43[医药卫生—临床医学]