乳糖诱导重组人睫状神经营养因子在大肠杆菌中的可溶性表达

目的利用乳糖替代IPTG,诱导重组人睫状神经营养因子(Recombinanthumanciliaryneurotrophicfactor,rhC-NTF)在原核工程菌BL-TCS中可溶性表达,并选择最适的诱导表达条件。方法在不同的温度下,利用不同浓度的乳糖及0·5mmol/L的IPTG,诱导含有人CNTF基因的工程菌9h,比较菌体生长、乳糖消耗以及目标蛋白的表达规律。结果乳糖组的菌体A600值均高于IPTG组。乳糖诱导产生的rhCNTF主要以可溶形式表达,各浓度乳糖的诱导效果均能接近或超过IPTG的效果。以2%乳糖在25℃下诱导6h,可以达到比较好的诱导效果。结论乳糖可取代IPTG诱导人CNTF基因表达,并获得良好效果。

Soluble Expression of Recombinant Human Ciliary Neurotrophic Factor in E.coli Using Lactose as Inducer

Objective To express recombinant human ciliary neurotrophic factor(rhCNTF)in E.coli BL-TCS,in a soluble form,using lactose as inducer instead of IPTG,and optimize the condition for expression.Methods Induce the expression of rhCNTF in E.coli BL-TCS with various concentrations of lactose at different temperatures for 9 h,using 0.5 mmol/L IPTG as control.Compare the growth of bacteria,the consummation of lactose and the expression of target protein.Results All the A_(600) values of bacteria induced by lactose were significantly higher than that by IPTG and increased with the increasing lactose concentration.The rhCNTF under induction of lactose was mainly expressed in a soluble form,and the expression level was not less than that under induction of IPTG.The condition for expression was optimized as incubation at 25℃ for 6 h under induction of 2% lactose.Conclusion Lactose might be used as an inducer of expression of rhCNTF in E.coli instead of IPTG.