突变型人肿瘤坏死因子-α工程菌发酵培养的实验研究

目的　优化基因重组人突变型 4 71肿瘤坏死因子 α(TNF α)工程菌的发酵和表达条件。方法　通过改变培养基的组分、pH值、培养温度和诱导表达的条件等 ,采用测定细菌生物量和蛋白表达量等方法 ,确定最适的发酵和表达条件 ,并考察工程菌中重组质粒的遗传稳定性。结果　突变型 4 71rhTNF α工程菌在 pH值 7.5的SOC培养基中 ,30℃培养、4 2℃诱导 5h时 ,其表达量最大。而且 ,所构建的重组质粒在工程菌DH5α中传代稳定 ,目的蛋白的表达不受影响。结论　优化了基因重组人突变型 4 71rhTNF α工程菌的发酵和表达的最适条件 ,为进一步开发人突变型 4 71rhTNF α奠定了基础

Study on fermentation of recombinant bacterial strain of human mutant tumor necrosis factor-α

Objective To optimize the conditions for the fermentation of human mutant 471 TNF α engineering bacterial strain. Methods We measured the biomass of the engineering bacteria and detected the SDS PAGE of target protein to determine the optimal conditions for fermentation and expression by changing the cultures, the values of pH,the cultural temperatures and the time of induced expression. The inheritance stability of the recombinant plasmid of mutant 471 rhTNF α was also analyzed. Results The highest bacterial yield and expression ratio of mutant 471 rhTNF α in recombinant bacterial strain were observed in SOC medium with a pH value of 7.5 , the culture temperature 30?℃ and the highest expression yield of mutant 471 rhTNF α were obtained after 5 hour induction at 42?℃. Furthermore, the recombinant plasmid was proved to have been inherited steadily in DH5α with stable expression of the target protein. Conclusion We obtained the optimal conditions for the fermentation and expression of the engineering bacterial strain of human mutant 471TNF α, which lays a solid foundation for further research on mutant 471 rhTNF α.