刚地弓形虫Peroxiredoxin基因编码蛋白结构与抗原表位的生物信息学分析

Bioinformatics analysis of the structure and epitopes of the gene encoding peroxiredoxin protein from Toxoplasma gondii

目的从生物信息学角度分析刚地弓形虫Peroxiredoxin(TgPrx)基因编码蛋白的结构与抗原表位,预测该蛋白的免疫原性。方法利用蛋白分析专家系统(ExPASy)提供的ProtParam、SOSUI、Emini、MotifScan、SWISS-MOD-EL等生物信息学在线分析程序,结合Gene Runner、DNAMAN等生物信息学软件,分析、预测TgPrx蛋白的理化性质、可溶性、表面可及性,翻译后修饰位点、亲(疏)水性、二级结构、抗原表位及三维结构等。结果该蛋白由339个氨基酸组成,分子式为C1736H2676N464O468S21,分子质量单位为38.2084ku,等电点理论值为9.12,波长280nm时的吸光度(A)值为0.843,半衰期为7.2h,有3个表面可及性参数≥3的区域、6个翻译后修饰位点、多个亲水性高的区域、13个潜在抗原表位,为可溶性表达蛋白。结论刚地弓形虫Peroxiredoxin基因编码的TgPrx蛋白为可溶性表达蛋白,具有免疫原性,可作为弓形虫病疫苗候选抗原。

Objective To predict the immunogenicity of the peroxiredoxin protein coded for by the TgPrx gene extracted from Toxoplasma gondii （TgPrx） and characterize its structure and epitopes from a bioinformatics approach.MethodsThe physico-chemical properties,solubility,surface accessibility,post-translational modification sites,hydrophilicity /hydrophobicity,secondary structure,specific epitopes,and 3D structure of TgPrx protein were analyzed and predicted using the ExPASy bioinformatics tools ProtParam,SOSUI,Emini,MotifScan,HNN,and SWISS-MODEL in combination with bioinformatics software （Gene Runner,DNAMAN,etc.）.Results TgPrx protein consisted of 339 amino acids and had the following characteristics：molecular formula：C1736H2676N464O468S21;molecular mass：38.208 4 ku;theoretical isoelectric point：9.12;absorbance （A）：0.843 （280 nm）;half-life：7.2 hr.There were 3 regions with high surface accessibility≥3,6 post-translational modification sites,numerous highly hydrophilic regions,and 13 potential epitopes expressed as a soluble protein.Conclusion The TgPrx protein coded for by the TgPrx gene may serve as a potential antigen for toxoplasmosis vaccination because of its soluble protein expression and immunogenicity.