苯丙氨酸解氨酶重组大肠杆菌的培养

Culture of Recombinant E. Coli Strain Producing Phenylalanine Ammonia Lyase (PAL)

摘要:

为了提高苯丙氨酸解氨酶的产量和活力，对高效表达圆红冬孢酵母苯丙氨酸解氨酶基因的重组大肠杆菌JM109进行培养，优化了发酵培养基成分、培养条件以及发酵工艺，结果表明，最佳葡萄糖浓度为20 g/L，碳氮比为7.86，添加5 g/L酵母粉和蛋白胨有利于菌体产酶，最佳发酵液初始pH为7.5，接种量为10%。通过以上优化，重组大肠杆菌培养18 h时酶活可达到70 U/g（DCW），酶活比原工艺提高了1.6倍。

Abstract:

In order to improve the yield and activity of phenylalanine ammonia lyase (PAL) produced by recombinant E. coli strain, the culture conditions of recombinant E .coli strain carrying PAL gene of Rhodotorula toruloides was studied and optimized. The results showed that the optimal original glucose concentration, C/N ratio, the inoculation size and the initial pH value, fermentation time were 20 g/L, 7.86, 10%, 7.5 and 18 h, respectively. It was also found that the PAL activity was significantly improved by adding 5 g/L peptone and 5g/L yeast powder in fermentation medium. Under the optimized conditions, the PAL activity reached 70 U/g (DCW), which is 1.6 times higher than that under original fermentation conditions.