L-谷氨酰肼为底物酶法制备茶氨酸  

Enzymatic Synthesis of Theanine with L-Glutamlhydrine as Substrate

作　　者：张飞[1,2] 熊吉滨[1] 刘均忠[1] 赵根海[1] 焦庆才[1] 

机构地区：[1]南京大学生命科学学院医药生物技术国家重点实验室,江苏南京210093 [2]包头轻工职业技术学院生物工程系,内蒙古包头014043

出　　处：《精细化工》2010年第2期130-132,141,共4页Fine Chemicals

基　　金：国家技术创新基金资助项目(02CJ-13-01-16)~~

摘　　要：采用一种廉价的底物L-谷氨酰肼代替L-谷氨酰胺,成功地合成了茶氨酸,并且对该酶促反应的条件进行了初步优化。结果表明,以L-谷氨酰肼为底物时,γ-谷氨酰转肽酶(GGT)活性约是以L-谷氨酰胺为底物时的78.3%。该酶促反应的最适条件为:pH=10,反应温度40℃,n(L-谷氨酰肼)∶n(乙胺)=1∶10,L-谷氨酰肼初始浓度0.3mol/L。利用以上条件进行了茶氨酸的小量制备,投料L-谷氨酰肼50g,乙胺140g,反应40h,L-谷氨酰肼的摩尔转化率达84.1%,经离子交换树脂分离产物,得到31.8g高纯度茶氨酸。该结果显示良好应用前景。In this research, an economical substrate, L-glutamlhydrine, was used in theanine synthesis catalyzed by Escherichia coli cells with L-glutamyhranspeptidase（GGT） activity. The result showed that GGT activity with L-glutamlhydrine as substrate was about 78. 3% of that with L-glutamine as substrate. In the optimized reaction condition with 0. 3 mol/L L-glutamlhydrine,3 mol/L ethylamine and 0. 018 g/ mL of GGT cells at pH = 10 and 40 ℃,0. 25 mol/L theanine was obtained in 40 h. The conversion rate from L-glutamlhydrine to theanine was 84. 1%. Theanine of high purity was obtained by ion exchange resin. The results exhibited a good prospect of application.

关 键 词：L-谷氨酰肼 茶氨酸 Γ-谷氨酰转肽酶 酶法合成 生物工程 

分 类 号：Q55[生物学—生物化学]