Rational Molecular Engineering of Glutamate Dehydrogenases for Enhancing Asymmetric Reductive Amination of Bulky α-Keto Acids
作者:Xinjian Yin、Yayun Liu、Lijun Meng、Haisheng Zhou、Jianping Wu、Lirong Yang
DOI:10.1002/adsc.201801251
日期:2019.2.19
for the synthesis of chiral α‐amino acids by asymmetric reductive amination of α‐keto acids. However, their strict substrate specificity limits their applications. To address this problem, we developed a molecular engineering method for GluDHs that enhances the asymmetric reductive amination of bulky α‐keto acids. Based on rational design, a “cave” located in the active site pocket of PpGluDH (GluDH from
谷氨酸脱氢酶(GluDHs)是通过α-酮酸的不对称还原胺化合成手性α-氨基酸的有前途的生物催化剂。但是,它们严格的底物特异性限制了它们的应用。为了解决这个问题,我们开发了一种用于GluDHs的分子工程方法,该方法可增强大体积α-酮酸的不对称还原胺化作用。基于合理的设计,“洞”位于Pp GluDH(恶臭假单胞菌的GluDH)的活性位点)在底物识别中起着至关重要的作用,经过了量身定制,以方便大体积底物的接受。发现两个突变体(A167G和V378A)对2-氧代-4-[[(羟基)(甲基)亚膦酰基]丁酸(PPO)和其他一些大的底物具有显着增强的催化活性。然后将该分子工程方法应用于来自不同来源和具有不同性质的十种其他GluDH。所有工程化的GluDHs在面向PPO的催化活性方面均取得了显着改善。最有效的NADP +(烟酰胺腺嘌呤二核苷酸磷酸)特异性GluDHs突变体的活性提高了1820倍,比活性达到111