一菌双酶法转化富马酸生成β-丙氨酸  

Biocatalytic synthesis of β-alanine from fumaric acid by a two-enzyme system

作　　者：陈明亮 祁瑛 肖延铭 华超 李敬亚[2] 梁阿朋 CHEN Mingliang;QI Ying;XIAO Yanming;HUA Chao;LI Jingya;LIANG Apeng(Zhejiang Engineering Research Center of Industrial Biocatalysis and Transformation, Changxing Pharmaceutical CO., Ltd.,Changxing 313100,China;College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China)

机构地区：[1]长兴制药股份有限公司工业生物催化与转化浙江省工程研究中心,浙江长兴313100 [2]郑州大学化学与分子工程学院,河南郑州450001

出　　处：《发酵科技通讯》2018年第4期231-235,共5页Bulletin of Fermentation Science and Technology

摘　　要：利用天冬氨酸转氨酶(AspAT)和L-天冬氨酸α-脱羧酶(PanD)偶联,以富马酸和氨作为底物催化合成β-丙氨酸(β-Ala)是工业合成β-丙氨酸的重要途径。但传统的双酶工艺需要分别发酵两个酶,且酶无法固定化。通过将AspAT和PanD构建入同一个大肠杆菌中,使其通过一次发酵就能产生两个酶,并且通过固定化通透细胞使酶可以重复利用。构建的工程菌的整体酶活为85.4U/g,固定化率为64.2%,固定化细胞最适反应温度为45℃,最适反应pH为7.5,最高可将质量浓度为300g/L的富马酸完全转化生成β-Ala,固定化细胞可连续使用12次。根据笔者提出的方法可简化酶的发酵工艺,进一步降低β-Ala的生产成本。L-Aspartase(AspAT)and L-aspartateα-decarboxylase(PanD)catalyzed transformation of fumaric acid and ammonia is an important approach for industrial production ofβ-alanine(β-Ala).However,the two enzymes were fermented separately and cannot be immobilized.In this study,AspAT and PanD was produced in one fermentation process by co-expression in E.coli,and the enzymes can be reused by immobilization.Activity of the recombinant cell was85.4U/g,and the immobilization yield reached64.2%.The optimum reaction temperature and pH of the immobilized cells was45℃and7.5,respectively.β-Ala was produced by the immobilized cells at high fumaric acid concentration of300g/L.The immobilized cells can be used continuously for12times.Based on these results,the fermentation process can be simplified,and the cost ofβ-Ala production can be further reduced.

关 键 词：天冬氨酸转氨酶 L-天冬氨酸 α -脱羧酶 通透细胞 固定化 

分 类 号：Q815[生物学—生物工程] Q819