人巨细胞病毒临床病毒株UL148基因B细胞表位的预测与分析

Prediction and Analysis of B-Cell Epitope in the UL148 Gene of Human Cytomegalovirus

目的预测与分析人巨细胞病毒(HCMV)临床病毒株UL148基因B细胞表位。方法应用生物信息学方法,以HCMV UL148基因氨基酸序列为基础,采用改进型自我优化预测结构(SOPMA),Garnier-Osguthorpe-Robson(GOR),人工神经网络预测法(HNN)预测二级结构,结合跨膜结构、Hopp&Woods亲水性方案、Emini可及性方案、Jameson-Wolf抗原性方案等参数综合预测UL148基因B细胞表位。结果 HCMV pUL148氨基酸包含316个氨基酸残基,相对分子质量为36kD,等电点为9.15;应用SOPMA,GOR,HNN方案预测pUL148二级结构,均显示以α-螺旋为主,无规则卷及β-转角区域多位于14～21,98～106,132～139,174～181,191～197,267～272,235～240。TMHMM预测pUL148存在一个跨膜区域,为286～308位氨基酸,胞外区域为1～285位氨基酸。结论 HCMV UL148基因265～275,221～229,18～25位氨基酸序列区域内或其附近主要以无规则卷或β-转角结构为主,且抗原指数(AI)较高,极有可能是B细胞表位。

Objective To investigate the B-cell epitope in the UL148 gene of human cytomegalovirus （HCMV）. Methods The secondary structure were analyzed by the improved self-optimized prediction method （SOPMA）, Garnier-Osguthorpe-Robson （GOR）, Hierarchical neutral network （HNN） Programs based on the amino acid sequence of HCMV UL148 gene. In combination with transmembrane, hydrophilicity, accessibility, flexibility and antigenicity analysis to selected the potential candidates of linear B-cell epitopes. Results HCMV pULl48 contains 316 amino acid residues, the relative molecular mass was 36 kD and the isoelectric point was 9.15;Variety of forecasting methods were prompted that the 14-21, 98- 106, 132-139, 174-181, 191-197, 267-272, 235-240 amino acid sequence regions were main random coil or p-turn model in the secondary structures The 1-285 amino acids was a transmembrane region and the extracellular regions was 1-285 amino acids, all of that were predicted by the TMHMM. Conclusions Comprehensive analysis that the 265-275,221-229,18-25 amino acid sequence regions were main random coil or β-turn model in the secondary structure, and consider of the average antigenicity index （AI） of epitope peptide investigation, three peptides were selected as potential candidates of linear B-cell epitopes.