乳糖诱导重组人SOD基因在大肠杆菌中的表达

Expression of Recombinant Human Superoxide Dismutase Gene in Escherichia coli Induced by Lactose

利用乳糖代替 IPTG诱导 rh Cu/ Zn- SOD在大肠杆菌 (Escherichia coli) BL2 1(DE3)中的表达 ,并将菌体生长情况及产物表达规律与 IPTG诱导进行比较。对诱导所需的乳糖浓度、金属离子浓度等因素进行了研究 ,并分析了低温下诱导对重组蛋白表达的影响。最终在摇瓶发酵条件的基础上 ,实现了乳糖诱导重组菌的 5 L 全自动发酵罐培养 ,rh Cu/ Zn- SOD酶活性达到 1810 U/ ml(发酵液 )。结果表明 ,乳糖可以诱导 rh Cu/ Zn- SOD在 Escherichia coli中的表达 ,并且酶活性达到 IPTG诱导时的 89%。

The possibility of using lactose as an inducer to substitute IPTG in the fermentation of rhCu/Zn-SOD in E.coli BL21(DE3) was investigated. The growth of E.coli and the expression of the recombinant protein were compared after induction by lactose or IPTG. The influences of concentrations of lactose and metal ions and induction temperatures on the expression of the recombinant protein were examined. Finally the recombinant E.coli was cultured in a 5 L fermentor. The maximum enzyme activity of rhCu/Zn-SOD reached 1810 U per ml fermentation broth. The results suggested that rhCu/Zn-SOD could be expressed in E.coli with lactose as a substitute inducer and the maximum enzyme activity was about 89% of that with IPTG.