亚洲牛带绦虫成虫延伸因子-1基因的表达、纯化及免疫学分析

Prokaryotic expression of elongation factor 1 gene of Taenia saginata asiatica and analysis of purification and immunogenicity of the recombinant protein

目的对亚洲牛带绦虫成虫延伸因子-1(elongation factor1,EF-1)基因进行克隆、表达和免疫学初步研究。方法将亚洲牛带绦虫成虫EF-1克隆到原核表达质粒pET-28a(+)中,在大肠杆菌BL-21/DE3中用异丙硫代-β-D半乳糖苷诱导表达,表达产物通过十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)进行鉴定,用镍离子金属螯合剂亲和层析柱进行纯化,用蛋白印迹法(Western blotting)进行免疫学分析。结果PCR、双酶切及DNA测序结果均表明重组质粒pET-28a(+)-EF-1构建成功。重组蛋白可被感染了亚洲牛带绦虫患者血清和猪血清识别,表明其具有免疫反应性。结论亚洲牛带绦虫成虫EF-1基因可在原核表达系统中获得具有免疫学活性的表达,为进一步研究该蛋白的功能奠定了基础。

Objective To clone and express the novel gene named elongation factor 1 （EF-1） of Taenia saginata asiatica in order to analyze the immunogenicity of the recombinant protein. Methods By screening the full length cDNA plasmid library, the coding region of EF-1 was amplified with PCR, and cloned into the prokaryotic expression vector pET-28a （＋） and then expressed in E. coli BL21 with IPTG induction. The recombinant protein was detected by SDS-PAGE and purified by Ni-IDA affinity chromatography, and its immunogenicity was analyzed by Western blotting. Results PCR, double enzyme digestion and DNA sequencing confirmed that the recombinant expression plasmid was successfully constructed. Western blot analysis of EF-1 recombinant protein testified that the recombinant protein could be recognized by immunizing the serum of swine and patient, therefore indicating its immunogenicity. Conclusion A novel gene coding EF-1 of Taenia saginata asiatica was cloned and expressed successfully. The purified protein of EF-1 will be of importance for further research on the biological function of the gene.