细粒棘球绦虫EgA31重组蛋白的抗原表位分析预测

Bioinformatics Prediction of EgA31 Recombinant Antigen Epitopes of Echinococcus granulosus

根据GenBank中细粒棘球绦虫EgA31序列(GenBank登录号为AF067807)设计引物,以细粒棘球绦虫mRNA为模板,RT-PCR扩增EgA31基因,将其克隆入pUCm-T载体,转化大肠埃希菌(E coli)DH5α,筛选阳性克隆,经BamH I、Sac I双酶切和PCR鉴定,获得阳性重组质粒pUCm-T/EgA31,并将测序正确的片段连接表达载体,成功构建重组质粒pET30a-EgA31。经序列分析和同源性比较,以及对其编码产物进行B细胞和T细胞表位分析,结果表明PCR扩增的特异条带为636 bp,与预期相符,与GenBank已知基因序列同源性为100%。编码产物B细胞和T细胞联合表位预测,氨基酸区域可能在32～79、79～95、105～124和141～154位。

Specific primers were designed and synthesized based on the reported EgA31 gene of Echirtococcus granulosus （GenBank Accession No. AF067807）. Total RNA was extracted from E. granulosus and its EgA31 gene was amplified by reverse transcription-polymerase chain raction （RT-PCR）. The PCR product was purified and cloned into plasmid pUCM-T, then transformed into Escherichia coli DHScc The recombinant plasmids were screened and identified by digestion with restriction enzyme and PCR amplification. The positive recombinant plasmid pUCM-T/EgA31 was confirmed by sequencing and homology comparison. Five parameters and methods were used to predict B-cell epitopes in amino acid sequence of EgA31. The amplified DNA fragment （636 bp） had an identity of 100% with the EgA31 gene sequence of E. granulosus. B-cell and T-cell epitopes of EgA31 were probably at or adjacent to 32-79, 79-95, 105-124 and 141-154 in its amino acid sequence.