刚地弓形虫动力蛋白轻链8a的生物信息学分析

Bioinformatic analysis of dynein light chain 8a of Toxoplasma gondii

目的通过生物信息学在线程序及软件分析弓形虫动力蛋白轻链8a(TgDLC8a),预测其结构、免疫原性及抗原性。方法利用生物信息学在线软件ProtParam、SOSUI、ProtScale、TMHMM Server v.2.0、SignalP-5.0、TargetP1.1、Coils、SOPMA、NetPhos 3.1Server、SWISS-MODEL、SYFPEITHI及DNAMAN软件、DNAStar软件等分析预测TgDLC8a蛋白的理化性质、亲疏水性、跨膜结构域、信号肽、亚细胞定位、可溶性、柔韧性、表面可及性、二级结构、蛋白翻译后修饰位点、三级结构及B细胞和T细胞抗原表位。结果TgDLC8a蛋白含有138个氨基酸,分子式为C723H1128N192O195S11,相对分子质量为15.92874×10^3,理论等电点为8.69,半衰期为30h,不稳定系数为37.09,脂溶性指数为88.33,总平均亲水性系数为0.025,属于疏水性蛋白;该蛋白有跨膜结构域,无信号肽切割位点,亚细胞定位预测可能是分泌蛋白;二级结构中α螺旋和β折叠分别占41.30%和23.91%,β转角和无规则卷曲分别占5.80%和28.99%;三级结构以二聚体的形式存在。该蛋白含有7个磷酸化修饰位点,其中4个丝氨酸磷酸化位点,2个苏氨酸磷酸化位点,1个酪氨酸磷酸化位点;含有7个B细胞抗原表位,7个CTL细胞抗原表位,11个Th细胞抗原表位。结论生物信息学预测TgDLC8a蛋白具有多个潜在的B细胞抗原表位及CTL细胞和Th细胞抗原表位,具有免疫原性和抗原性,可作为为抗弓形虫病疫苗候选蛋白。

Objective To bioinformatically analyze the dynein light chain 8a protein of Toxoplasma gondii(TgDLC8a)with on-line programs and software in order to predict its structure,immunogenicity,and antigenicity.Methods The physicochemical properties,hydrophilicity and hydrophobicity,transmembrane domains,signal peptides,intracellular localization,solubility,flexibility and surface accessibility,secondary structure,post-translational modification sites,tertiary structure,and specific epitopes of TgDLC8awere analyzed and predicted with bioinformatic on-line programs and software such as ProtParam,SOSUI,ProtScale,TMHMM Server v.2.0,SignalP-5.0,TargetP 1.1,Coils,SOPMA,NetPhos 3.1Server,SWISS-MODEL,SYFPEITHI,DNAMAN,and DNAStar.Results TgDLC8a consists of 138amino acids with a molecular formula of C 723 H 1128 N 192 O 195 S 11,a molecular mass of 15.92874×10^3,a theoretical isoelectric point of 8.69,an estimated half-life of 30h,an instability index of 37.09,a liposolubility index of 88.33,and a total average hydrophilicity index is 0.025,indicating that the protein is hydrophobic.TgDLC8ahas a trans-membrane domain and no signal peptide cleavage sites.Subcellular localization predicted that TgDLC8amay be a secreted protein.The secondary structure of TgDLC8aconsists of alpha helices(41.30%),beta folds(23.91%),beta turns(5.80%),and random coils(28.99%).The tertiary structure of the protein is a dimer.TgDLC8acontains 7phosphorylation sites,including 4serine phosphorylation sites,2threonine phosphorylation sites,and 1tyrosine phosphorylation site.The TgDLC8aprotein also contains 7Bcell epitopes,7CTL cell epitopes and 11Th cell epitopes.Conclusion TgDLC8aconsists of multiple epitopes,may be a highly immunogenic protein,and a is a potential candidate for vaccines.