乳糖诱导对虾白斑病毒囊膜蛋白VP28基因在重组大肠杆菌中的表达

Lactose-induced expression of envelope protein VP28 gene of white spot syndrome virus (WSSV) in recombinant Escherichia coli BL21

以含对虾白斑综合症病毒(white spot syndrome virus,WSSV)囊膜蛋白VP28编码基因质粒的重组大肠杆菌Escherichia coliBL21作为研究对象,研究了乳糖或乳清粉代替IPTG作为诱导剂诱导重组囊膜蛋白VP28的表达。结果表明,乳糖不仅能够作为诱导剂诱导重组大肠杆菌进行外源蛋白的表达,而且能作为碳源促进菌体的生长。通过对诱导条件的优化,乳糖在发酵培养基的添加量为8g.L-1,发酵时间为12h时可以获得最高的目的蛋白表达量,为97.36mg.L-1。试验亦使用乳清粉作为发酵培养基的碳源和诱导工程菌表达的诱导剂。结果表明,在发酵培养基中添加乳清粉作为碳源和诱导剂,使其乳糖终浓度为10g.L-1,发酵时间为13h时可以获得最高的目的蛋白表达量,为86.24mg.L-1。

This paper reported the expression of envelope protein VP28 of white spot syndrome virus （WSSV） in recombinant Escherichia coll B121 by using lactose as inducer. The results indicated that lactose could induce foreign protein expression and enhance cell growth during the induction period. The study showed that expression of VP28 fusion protein was up to 97.36 mg·L^-1 with the lactose concentration of 8 g·L^-1 and the optimal fermentation condition of 12 hours. In order to reduce the cultivation cost, the whey was used as alternative to lactose as carbon source and inducer for VP28 expression. The results showed that expression of VP28 fusion protein was up to 86.24 mg·L^-1 with the whey concentration of 10 g·L^-1 and the optimal fermentation condition of 13 hours.