弓形虫致密颗粒蛋白GRA12的生物信息学分析

Bioinformatics analysis of dense granule protein GRA12 of Toxoplasma gondii

为分析并预测弓形虫致密颗粒蛋白GRA12基因编码蛋白的结构、功能以及其作为疫苗候选抗原的可能性,本研究从Gen Bank数据库获取GRA12基因序列,通过在线蛋白分析专家系统(Expasy)并结合GENERUNR、DNAStar、DNAMAN等生物信息学分析软件对GRA12序列的编码区进行分析、对该基因编码蛋白质的理化性质、信号肽、跨膜结构域、二级结构、亲/疏水性、抗原表位等信息预测。结果表明:该基因全长1 311 bp,编码436个氨基酸,蛋白性质稳定,理论分子质量约为47.8 ku,无信号肽,有6个跨膜区,14个丝氨酸磷酸化位点、7个苏氨酸磷酸化位点、3个酪氨酸磷酸化位点、18个O-糖基化位点、3个乙酰化蛋白附着位点、1个酪氨酸硫酸化位点、1个潜在的N-糖基化位点、1个棕榈酰化位点,15个潜在的抗原表位。研究结果分析说明GRA12有潜力成为弓形虫疫苗候选抗原。

In order to explore the possibility as a vaccine candidate antigen of the dense granule protein 12（GRA12） of Toxoplasma gondii,the GRA12 gene sequence was obtained from the Gen Bank database,and then an online expert system for protein analysis was utilized to analyze the coding region of the gene sequence in combination with other bioinformatics softwares including GENE Runner,DNAMAN,DNASTAR,and so on.The physical and chemical properties,signal peptide,transmembrane domain,secondary structure,hydrophilicity/hydrophobicity and antigen epitopes of the gene encoding protein were predicted.The results showed that the gene was 1311 bp in full length.It encodes a protein of 436 amino acids.The encoded protein has stable physical and chemical properties,and has a theoretical molecular mass of 47.8 ku without signal peptides.The GRA12 protein has 6 transmembrane regions,14 serine phosphorylation sites,7 threonine phosphorylation sites,3 tyrosine phosphorylation sites,18 O-glycosylation sites,3 acetylated protein attachment sites,1 tyrosine sulfation sites,1 potential N-glycosylation sites,1 palmitoylation sites and 15 potential antigen epitopes.The analysis provides the theoretical basis for GRA12 as a protective antigen of T.gondii.