摘要
[目的]为了降低工业用谷氨酰胺合成酶的成本。[方法]利用酵母下脚料制得废酵母基来培养BL21(DE3)-pET28b-glnA,用乳糖诱导合成GS,并对诱导生长点、诱导浓度、诱导时间、添加碳源氮源以及所得GS的可溶性和酶活进行研究。[结果]酵母下脚料可以替代LB培养基诱导产生重组GS,其最佳诱导条件为:OD600=0.5,乳糖1 g/L诱导12 h;并不需要补加其他碳氮源,GS可溶性90%以上,催化Glu转化为Gln的转化率为94.5%。[结论]生产用高活性干酵母经过短期发酵后,酵母下脚料中的营养活性物质依然很丰富,可以用来培养大肠杆菌诱导目的蛋白表达,从而降低工业用谷氨酰胺合成酶的成本。
The aim was to reduce the cost of glutamine synthetase （GS） used in industry. [ Method] The waste yeast medium was made from yeast waste for culturing BI.21（DE3）-pET28b-glnA, which was induced by lactose to synthesize GS and study the induced growth point, inducing concentration and time, added carbon and nitrogen sources and the solubility and enzyme activity of the obtained GS. [Result] The yeast waste could replace LB medium to induce producing recombined GS and its optimum inducing conditions were as follows： OD600 =0.5 and inducing with 1 g/L lactose for 12 h. It was not necessary to supplement the other carbon and nitrogen sources, and the solubility of GS was over 90% with the transformation rate of catalyzing Glu to transform into Gin being 94.5%. [Conclusion] After short-time fermentation of dry yeast with high activity in production, the nutritive active matter in the yeast waste was also very abundant, which could be used to culture Escherichia coli and induce the expression of objective protein. Consequently, the cost of glutamine synthetase used in industry was reduced.
出处
《安徽农业科学》
CAS
北大核心
2008年第4期1360-1364,共5页
Journal of Anhui Agricultural Sciences
