产1,3-丙二醇新型重组大肠杆菌JM109(pHsh-dhaB-yqhD)的构建及其转化甘油

利用温控载体pHsh将编码甘油脱水酶的基因dhaB和编码1,3-丙二醇氧化还原酶同工酶的基因yqhD串联构建重组质粒pHsh-dhaB-yqhD, 将其转化大肠杆菌得到新型产1,3-丙二醇重组大肠杆菌JM109(pHsh-dhaB-yqhD), 并对影响该重组菌发酵的营养因子进行研究.实验结果表明：该重组菌转化甘油合成1,3-丙二醇的适宜培养基组成为甘油60 g·L^-1、酵母膏5.0 g·L^-1、维生素B₁₂ 0.05 g·L^-1以及KH₂PO₄ 7.5 g·L^-1; 以此培养基在5 L发酵罐上进行放大, 1,3-丙二醇产量、转化率和生产能力分别达到43.26 g·L^-1、72.2 %和1.55 g·L^-1·h^-1.

Construction of novel recombinant Escherichia coli capable of producing 1,3-propanediol and its conversion of glycerol

The gene dhaB encoding glycerol dehydrase from Citrobacter freundii gene dhaB and 1,3-propanediol (1,3-PD)oxidoreductase isoenzyme encoding gene (yqhD) were transferred into temperature control expression vector pHsh to construct a novel recombinant Escherichia coli JM109 (pHsh-dhaB-yqhD).Some nutrient ingredients affecting fermentation results of this recombinant strain were also studied.The results demonstrated that the optimized medium comprised(g·L^-1) glycerol 60, yeast extract 5.0, KH₂PO₄ 7.5 and vitamin B₁₂ 0.05.The 1,3-propanediol concentration, yield on glycerol and productivity in the 5 L fermenter could reach 43.26 g·L^-1, 72.2 % and 1.55 g·L^-1·h^-1 respectively.