重组菌BL21-HTa-cgkZ产κ-卡拉胶酶的发酵条件优化

Optimization of fermentation conditions of κ-carrageenase by recombinant strain BL21-HTa-cgkZ

【目的】优化重组菌BL21-HTa-cgkZ产生κ-卡拉胶酶的发酵条件。【方法】通过单因子筛选和响应面分析方法对在IPTG诱导下的κ-卡拉胶酶的产生菌BL21-HTa-cgk Z进行产酶条件优化。【结果】该菌产酶的最佳培养基组成为:乳糖7 g/L,胰蛋白胨10 g/L,酵母粉5 g/L,NaCl10 g/L,CaCl2 0.666 g/L。最佳诱导条件为:在工程菌接种1.55 h后添加IPTG,IPTG的浓度为0.89 mmol/L,诱导时间为24 h,诱导温度为23.03°C。并确定了在培养基中添加乳糖、Triton X-100对κ-卡拉胶酶分布的影响。【结论】实验结果为产κ-卡拉胶酶工程菌的规模化生产奠定基础。

[Objective] To obtain the high-yield κ-carrageenase by the recombinant strain BL21-HTa-cgkZ. [Methods] The optimal fermentation conditions of the recombinant strain BL21-HTa-cgkZ were determined by using single factor design and response surface analysis in the flask. [Results] The optimal medium compositions were composed of lactose 7 g/L, tryptone 10 g/L, yeast extract powder 5 g/L, NaC1 10 g/L and CaCI2 0.666 g/L. The optimal induction condition was adding IPTG 0.89 mmolfL after inoculation for 1.55 h and maintaining the fermentation at 23.03 ℃ for 24 h. The distribution of -carrageenase expressed by recombinant strain BL21-HTa-cgkZ was also affected by the additive such as lactose and triton X-100 in the medium. [Conclusion] The results provide the clues for the mass production of K-carrageenase by the recombinant strain BL21-HTa-cgkZ.