重组大肠杆菌中NTA的发酵与表达优化

研究诱导剂、诱导剂浓度、诱导时间、锌离子以及在发酵培养基中组合添加乳糖对提高重组新型溶栓酶外源蛋白的表达效率的作用，结果表明：IPTG诱导效果优于乳糖，IPTG诱导浓度选择1．5mmol·L^-1，诱导时机选择菌体OD600接近4．0时，诱导后的最佳培养时间为6h，加入1．0g．L^-1的ZnCl2后，外源蛋白表达可提高40％，发酵结果提高29．8％．在培养基中组合加入微量的乳糖，可以使外源蛋白的表达效率提高10％~15％．

Optimization of Fermentation Condition and Expression of NTA in Recombonant Escherichia coli

The study is conducted on inducing agent, inducer concentration, induction time, zinc ion and lactose added to fermentation medium to improve the expression of the New Thrombolytic Agent. The test results show that IPTG induced is more effective than lactose, inducer concentration is 1.5 mmol·L^-1 with bacterial OD600 being close to 4.0. The optimal culture time after the induction is found to be 6 hours. By adding 1.0 g·L^-1 of ZnCl2, the expression of exogenous protein increases by 40%, and fermentation increases by 29.8%. With addition of slight amount of lactose in the fermentation medium, the efficiency of protein expression is found to increase by 10%-15%.