乙肝病毒核心蛋白序列特征的生物信息学分析

Sequence characterization of core protein in hepatitis B virus

目的乙型肝炎病毒C基因编码的核心(HBc)蛋白抗原性强,也与持续性病毒感染有关。采用生物信息学方法分析HBc蛋白的结构和序列特征,有助于HBc蛋白的优化表达和纯化,并为乙肝患者的治疗以及疫苗的研制提供参考。方法乙肝病毒HBc序列的获取来源于NCBI网站GenBank数据库。运用Prot-Param和ProtScale工具在线预测乙肝病毒HBc的理化性质及其亲疏水性;通过在线软件SignalP 4.0Server和TMHMM分别分析该序列的信号肽特征,跨膜区域及磷酸化位点;利用SOPMA和SWISS-MODEL全自动在线软件预测其二级结构和三级结构模型;利用IEDB Analysis Resource,ABCpred和SYFPEITHI HLA-A;02:01预测该蛋白抗原表位,利用Venny2.1.0工具筛选该蛋白最佳表位形成位置等。结果HBc蛋白由212个氨基酸组成,分子式为C_(1086)H_(1710)N_(314)O_(300)S_(12),分子质量单位为24.35017ku,理论等电点为9.49。为不稳定亲水性蛋白质。该蛋白质具有信号肽,没有跨膜区域,具有40个潜在的磷酸化位点。预测其主要二级结构为α螺旋和无规卷曲,含量分别36.32%和41.04%。结合HBc蛋白序列的T、B细胞表面抗原、表面可及性、β转角、线性表位的预测结果,发现HBc蛋白具有T、B细胞抗原表位,并且存在4个潜在的优势抗原决定簇区域,分别为37-38、110、158-164、180-208位氨基酸。结论生物信息学方法预测HBc蛋白存在潜在的抗原表位区域,具有多个磷酸化位点。这有利于疫苗的研发与制备。

Objective The core(HBc)protein encoded by the hepatitis B virus C gene has strong antigenicity and is also related to persistent viral infection.Bioinformatics methods were used to analyze the structure and sequence characteristics of HBc protein,It is helpful for the optimal expression and purification of HBc protein,provides reference for the treatment of hepatitis B patients,and the development of vaccines.Methods Get the sequence of hepatitis B virusHBc from the Genbank database intheNCBI website,We have predicted the physicochemical properties and hydrophobicity of hepatitis B virus HBc using the online tools Prot-Param and ProtScale,and analyzed the signal peptide properties,transmembrane region,and phosphorylation sites of the sequence using the online software SignalP 4.0 Server and TMHMM,respectively.To predict the secondary structure and the three-level structure model,SOPMA and Swiss-Model fully automatic online software were used.IEDB Analysis Resource,ABCpred,and SYFPEITHI HLA-A*02:01 were used to predict the epitope,and the Venny 2.1.0 tool was used to screenthe best epitope formation position of the protein.Results HBc protein is composed of 212 amino acids,its molecular formula is C_(1086)H_(1710)N_(314)O_(300)S_(12),its molecular mass unit is 24.35017 ku,and its theoretical isoelectric point is 9.49.It is an instabile hydrophilic protein.This protein has a signal peptide,no transmembrane region,and 40 phosphorylation sites.It is predicted that its main secondary structure is an alpha-helix and random coil,the contents of which are 36.32%and 41.04%,respectively.According to the predictions of T and B cell surface antigens,surface accessibility,theβ-turn,and linear epitope combined with the HBc protein sequence,it is found that HBc has T and B cell epitopes,and there are 4 potential epitope regions,respectively,37-38,110,158-164,180-208 amino acids.Conclusion HBc has multiple phosphorylation sites in the epitope region,which makes it a good candidate for vaccine development and preparation.Bioinformatics methods confirm this finding.