考察了自动诱导培养基代替异丙基-β-D-巯基半乳糖苷(IPTG)培养基诱导四氢叶酸还原酶在重组大肠杆菌BL21(DE3)中表达的可行性,对自动诱导培养基自诱导时的乳糖浓度和葡萄糖添加量进行优化,并与IPTG诱导培养基进行比较,确定了自动诱导培养基配方:葡萄糖1.8 mmol/L、乳糖3 mmol/L、胰蛋白胨10 g/L、酵母膏5g/L、NaCl 10 g/L。HPLC结果显示,自诱导与IPTG诱导条件下的L-5-甲基四氢叶酸产量接近。 The feasibility of inducing the expression of tetrahydrofolate reductase in recombinant E. coli BL21 (DE3) by using the induction medium instead of isopropyl-β-D-thiogalactopyranoside (IPTG) The lactose concentration and the amount of glucose at the induction were optimized and compared with the IPTG induction medium to determine the automatic induction medium formula: glucose 1.8 mmol / L, lactose 3 mmol / L, tryptone 10 g / L, yeast extract 5g / L, NaCl 10 g / L. The results of HPLC showed that the yield of L-5-methyltetrahydrofolate by self-induction was similar to that of IPTG.