摘要
目的应用生物信息学方法分析刚地弓形虫亲环蛋白(cyclophilin protein,TgCyP)基因编码蛋白的主要特性与抗原表位,筛选该蛋白的T/B细胞联合表位。方法利用蛋白分析专家系统(ExPASy)提供的ProtParam、SignalP、SOSUI、SOPMA、PSORT、MotifScan和NCBI上的ORF finder、Bcepred、SYFPEITHI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,分析和预测TgCyP蛋白的理化性质、信号肽、可溶性、表面可及性、可塑性,跨膜区,翻译后修饰位点、亲(疏)水性、二级结构、亚细胞定位、T/B细胞抗原表位等。结果该蛋白由179个氨基酸组成,分子式为C884H1378N242O258S4,分子质量单位为19.6523ku,等电点理论值为6.06,波长280nm时的吸光度(A)值为0.787,半衰期为30h,有4个表面可及性参数≥1.9的区域、4个亲水性参数得分≥1.9的区域、7个柔韧性参数得分≥2的区域、9个翻译后修饰位点、8个潜在B细胞表位、3个T/B细胞联合表位,为可溶性表达蛋白。结论 TgCyP蛋白为可溶性表达蛋白,有3个T/B细胞联合表位,具有潜在的免疫保护作用。
Objective To predict the main characteristics of a cyclophilin of Toxoplasma gondii （TgCy） encoded by a gene and its T/B cell epitopes using bioinformatics. Methods The physico-chemical properties, solubility, surface accessibility, flexibility, post-translational modification sites, signal peptides, transmembrane domains, hydrophilicity/hydrophobicity, secondary structure, subcellular localization, and T/B cell epitopes of TgCy were analyzed and predicted using bioinformatics tools from ExPASy, including ProtParam, SOSUI, SOPMA, PSORT, MotifScan, ORF finder, SignalP, and Bcepred. Analysis was also done with bioinformatics software （Gene Runner, DNAMAN, etc.）. Results TgCy consisted of 179 amino acids and had a molecular formula of C884H1378N242O258S4, a molecular mass of 19.652 3 kDa, a theoretical isoelectric point of 6.06, an absorbance （A） of 0.787 （280 nm）, and a half-life of 30 hr. The protein had 4 zones with surface accessibility ≥ 1.9, 4 zones with hydrophilicity ≥1.9, 7 zones with flexibility≥2, 9 post-translational modification sites, 8 potential B cell epitopes,and 3 combined T/B cell epitopes, indicating expression of a soluble protein. Conclusion TgCy is a soluble protein with the potential for immune protection because of its 3 combined T/B cell epitopes.
出处
《中国病原生物学杂志》
CSCD
北大核心
2013年第5期407-410,共4页
Journal of Pathogen Biology
基金
国家自然科学基金项目(No.81071374)
