多拷贝水蛭素基因在毕赤酵母中的分泌型表达

目的:通过多拷贝克隆技术实现水蛭素(Hirudin)基因在巴斯德毕赤酵母中的高效分泌表达.方法:利用基因重组技术,从pPIC9-Hirudin中扩增α-facor-Hirudin插入到载体pA0815中,并构建pA0815-(α-Hirudin)n多拷贝重组质粒,转化毕赤酵母GS115后进行诱导表达,并鉴定表达产物活性.结果:PCR证实成功构建了水蛭素多拷贝毕赤酵母表达载体pA0815-(α-Hirudin)n,经SDS-聚丙烯酰胺凝胶电泳证实能成功高效分泌重组水蛭素,活性测定表明表达的水蛭素有良好的抗凝血活性.结论:成功构建了分泌型水蛭素多拷贝质粒,筛选出多拷贝稳定整合表达菌株,成功表达出具有抗凝血活性的1 600 ATU/mL重组水蛭素,为大规模表达纯化水蛭素蛋白及其临床应用奠定了基础.

Construction of a Multi-Copy Secretory Expression Vector and Hirudin Expression in Pichia Pastoris

Objective:To construct suitable vectors for the secretory expression of hirudin in Pichia pastoris.Methods:The α-facor-hirudin gene was amplified from pPIC9-hirudin by PCR and sub-cloned into PA0815.The multi-copy recombinant plasmid pA0815-(α-Hirudin)n was constructed.The recombinant was transformed into P.pastoris strain GS115 for induction expression and then the activity of secreted products was identified.Results:A new multi-copy vector pA0815-(αHirudin)n was successfully constructed and was capable of secreting recombinant hirudin efficiently,which was confirmed respectively by PCR and SDS-PAGE.The products possessed the activity of thrombin inhibitor.Conclusion:This result offers efficient P.pastoris stains for mass production of biological active hirudin.