摘要
目的获取结核分枝杆菌(H37Rv)的eis基因序列及其编码蛋白(Eis蛋白)的氨基酸序列,预测和分析该蛋白的结构和功能。方法从NCBI BenBank数据库获取eis基因及其编码蛋白序列,利用ORF Finger工具分析eis基因的开放阅读框;利用Expasy PortParam、SignalP 4.0Server、TMHMM Server v.2.0、SOPMA、BLAST、SWISS-MODEL、ABCpred、SYFPEITHI以及NetMHCIIpan 3.1Server等软件对Eis蛋白的生物学特性进行预测分析。结果结核分枝杆菌eis基因全长1 164bp,有7个开放阅读框,最长一个被通读,编码387个氨基酸。Eis蛋白分子式C1870H2958N550O542S11,等电点(pI)为6.46,属于不稳定、疏水性蛋白;无跨膜区,信号肽切割位点位于第21位氨基酸处;二级结构预测无规则卷曲占30.23%,含有一个保守结构域;建立同源三级模型,GMQE为0.98;预测该蛋白至少含有6个B细胞优势抗原表位和14个优势CTL表位。优势抗原表位数个。结论生物学信息学方法预测结核分枝杆菌的Eis蛋白具有优势T、B细胞抗原性表位,所含保守结构域与其功能密切相关。eis基因以及Eis蛋白与结核分枝杆菌抑制细胞自噬及其耐药机制密切相关,可作为抗结核治疗的切入点。
Objectivs To obtain the sequence of the eis gene of Mycobacterium tuberculosis（H37 Rv）and the amino acid sequence of the Eis protein and to predict and analyze the structure and function of the Eis protein. Methods The sequence of the eis gene and the amino acid sequence of the Eis protein were obtained from the NCBI database.ORF Finger was used to analyze the open reading frame of the eis gene.Analysis of the physical and chemical properties of the Eis protein and determination of its primary structure were accomplished using Expasy ProtParam software.The hydrophobicity of the Eis protein was analyzed using ProtScalene Expasy.SignalP 4 Server and TMHMM Server v.2.0 were used to predict the signal peptides and transmembrane regions of the Eis protein.SOPMA and SWISS-MODEL were used to predict the secondary and tertiary structures of the Eis protein.Epitopes of the Eis protein were predicted using ABCpred and SYFPEITHI. Results The eis gene of M.tuberculosis was 1,164 bp in length and has 7 open reading frames.The longest was identified,and it encoded 387 amino acids.The molecular formula for the Eis protein was C1870 H2958 N550 O 542 S11,and the protein consisted of 387 amino acids.The isoelectric point（PI）of the Eis protein is 6.46.The Eis protein is an unstable and hydrophobic protein.The Eis protein has no transmembrane regions,and a signal peptide cleavage site is located at amino acid 21.Its secondary structure mostly consists of random coils,which account for about 30.23% of the structure.The Eis protein contains a conserved domain,suggesting that the protein belongs to the NAT coenzyme family.A homologous tertiary model of the Eis protein was created,and the GMQE was 0.98.The predicted Eis protein contains at least 6 B-cell dominant antigen epitopes and 14 dominant CTL epitopes. Conclusion Bioinformatics predicted that the Eis protein of M.tuberculosis contains at least 6 B-cell dominant antigen epitopes and 14 dominant CTL epitopes.The Eis protein may have a domain belonging to the NAT coenzyme fa
作者
张西燕
付玉荣
伊正君
ZHANG Xi yan1 , FU Yu-rong2 , YI Zheng-jun1(1. Department of Medical Laboratory Science, Weifang Medical University, Wei fang, Shandong 261053, China ; 2. Department of Pathogen Biology, Wei fang Medical University)
出处
《中国病原生物学杂志》
CSCD
北大核心
2018年第2期140-145,151,共7页
Journal of Pathogen Biology
基金
国家自然科学基金项目(No.30972639)
山东省自然科学基金项目(No.ZR2016HM09)
