丝氨酸脱氨酶酶法拆分DL-丝氨酸

Enzymatic resolution of DL-serine with recombinant serine deaminase activity

摘要:

利用pET28a为载体在宿主细胞BL21 (DE3)中重组表达了大肠杆菌丝氨酸脱氨酶，以L-丝氨酸为底物研究了其酶学性质，考察了温度、起始pH、底物浓度等因素对酶促反应的影响，并利用丝氨酸脱氨酶酶法拆分了DL-丝氨酸。结果表明：丝氨酸脱氨酶重组表达成功；丝氨酸脱氨酶最佳反应条件为37℃，pH=9.0，底物浓度4%；0.3 g菌体细胞酶法拆分100 ml ? (DL-丝氨酸) =8%反应液需8 h，其中L-丝氨酸摩尔转化率达98%。

Abstract:

The serine deaminase from Escherichia coli K-12 MG1655 was recombinant expressed in Escherichia coli BL21 (DE3) using plasmid pET28a as vector. The enzymatic properties of recombinant serine deaminase were studied, and several influence factors of enzyme reaction such as temperature, initial pH, concentration of L-serine were investigated. Then DL-serine was resoluted with recombinant serine deaminase. The results indicated that the recombinant serine deaminase was successfully expressed, and the optimal conditions for enzymatic conversion of L-serine were 37oC, initial pH=9.0 and ? (L-serine) =4%. 0.3 g serine deaminase cell enzymatic conversion 100 ml ? (DL-serine) =8% needs 8 h, and the mole conversion rate of L-serine is up to 98%.