包括辅酶原位再生的偶联酶反应联产1，3-二羟基丙酮和2-氨基丁酸

Coupled Enzymatic Reactions for Simultaneous Synthesis of 1,3-Dihydroxyacetone and 2-Aminobutyric Acid with in situ Regeneration of Coenzyme

将甘油脱氢酶(GDH)和亮氨酸脱氢酶(LDH)偶联,以甘油和2-丁酮酸为底物,同时合成1,3-二羟基丙酮(DHA)和2-氨基丁酸,并实现辅酶NAD+的循环再生.考察了底物和辅酶NAD+浓度对产物产率和辅酶总转换数(TTN)的影响,结果表明,当NAD+初始浓度为0.1μmol/L时,TTN值可达5110;底物甘油和2-丁酮酸的转化率分别为1.4%和2.6%.通过分析各反应底物和产物对GDH和LDH反应初速率的影响,认为产物DHA和2-氨基丁酸对GDH和LDH的强烈抑制效应是造成反应转化率低的主要原因.因此,采取有效的产物去除措施将是提高偶联反应效率的关键.

Simultaneous synthesis of 1,3-dihydroxyacetone （DHA） and 2-aminobutyric acid from glycerol and 2-oxobutyric acid was achieved by coupling the reactions of two enzymes, glycerol dehydrogenase and leucine dehydrogenase with in situ regeneration of coenzyme. The effects of concentrations of substrates and coenzyme NAD＋ on the yields of the products and the total turnover number （TTN） of the multi-enzyme reaction system were examined. The results show that the TTN value could reach 5 110 with an initial NAD^＋ concentration of 0.1 μmol/L. The observed yields of products were 1.4% and 2.6% for glycerol and 2-oxobutyric acid respectively, based on the amount of substrates used. The strong inhibitory effects of DHA and 2-aminobutyric acid on GDH and LDH were regarded as the main causes for such low product yields. Accordingly, an effective removal strategy of products will be necessary for future improvement of the efficiency of the reaction system.