固定化色氨酸合成酶基因工程菌合成L-色氨酸的研究

Immobilization of gene engineering bacteria with Tryptophan synthetase and the synthesis of L – tryptophan

摘要:

以海藻酸钠作为包埋剂、戊二醛作为交联剂和氯化钙作为填充剂对色氨酸合成酶基因工程菌进行固定化，同时探究三种物质和菌体负载量对固定化菌影响，响应面法优化色氨酸合成酶基因工程菌合成L-色氨酸。固定化色氨酸合成酶基因工程菌最优制备条件为：海藻酸钠28.92 g/l、戊二醛0.95%、氯化钙19.82 g/l、菌体负载量25 g/l。底物L-丝氨酸浓度为1%、固定化菌8g， L-色氨酸转化率为28.16%。固定化菌可连续使用15批次。

Abstract:

Using sodium alginate as embedding agent, glutaraldehyde as crosslinking agent and calcium chloride as filling agent immobilize the genetic engineering bacteria with tryptophan synthetase. The effect of the concentration of sodium alginate, glutaraldehyde and calcium chloride and the bacteria load were investigated. And then these factors were optimized by response surface method, in order to determine the optimal immobilized conditions. After that, using the best immobilized bacteria synthesize L-tryptophan and making sure the optimum substrate concentration and the amount of immobilized bacteria. The best preparation conditions for the immobilized bacteria are 28.92 g/l sodium alginate, 0.95% glutaraldehyde, 19.82 g/l calcium chloride and 25 g/l bacteria load. The best synthesis conditions of tryptophan are 1% L-serine and 8 g immobilized bacteria. The average conversion rate from substrate is 28.16%. The immobilized bacteria can be used continuously for 15 times.