【摘要】 利用PCR技术以纳豆杆菌染色体DNA为模板扩增纳豆激酶基因 ,将该基因克隆到温度诱导型表达载体pBV2 2 0上 ,转化E .coliHB1 0 1 ,获得转纳豆激酶基因重组菌。在确定了其最佳培养时间与诱导时间后 ,SDS PAGE分析结果表明基因表达产物为分泌型 ,蛋白表达量占菌体蛋白的 1 2 %左右 ,液体发酵后纳豆激酶产量可达 1 2 0U/mL菌液。对重组菌中重组质粒的稳定性进行研究 ,结果表明该质粒在宿主菌中具有良好的分离稳定性 ,而结构稳定性较差。更多还原

【Abstract】 In this study, nattokinase gene was amplified by PCR using bacillus subtilis chromosomal DNA as template and cloned into expressed vector pBV220. After transforming recombinant plasmid into E.coli HB101, the recombinant strain was yielded. It was proved that expression products was secretive and expression protein was 12% of total cell protein by SDS-PAGE. Optimum culture time and inducing time was determined as 6h and 5h respectively. The plasmid stability studies showed that recombinant plasmid has excellent segregational stability but the structural stability was not good in the host cell.更多还原