辅因子
化学
胺化
催化作用
吡哆醛
生物催化
胺气处理
蛋白质工程
组合化学
转氨酶
立体化学
酶
有机化学
反应机理
作者
Tim Börner,Sebastian Rämisch,Sebastian Bartsch,Andreas Vogel,Patrick Adlercreutz,Carl Grey
出处
期刊:ChemBioChem
[Wiley]
日期:2017-06-13
卷期号:18 (15): 1482-1486
被引量:34
标识
DOI:10.1002/cbic.201700236
摘要
Abstract Amine transaminase (ATA) catalyse enantioselectively the direct amination of ketones, but insufficient stability during catalysis limits their industrial applicability. Recently, we revealed that ATAs suffer from substrate‐induced inactivation mechanism involving dissociation of the enzyme–cofactor intermediate. Here, we report on engineering the cofactor‐ring‐binding element, which also shapes the active‐site entrance. Only two point mutations in this motif improved temperature and catalytic stability in both biphasic media and organic solvent. Thermodynamic analysis revealed a higher melting point for the enzyme–cofactor intermediate. The high cofactor affinity eliminates the need for pyridoxal 5′‐phosphate supply, thus making large‐scale reactions more cost effective. This is the first report on stabilising a tetrameric ATA by mutating a single structural element. As this structural “hotspot” is a common feature of other transaminases it could serve as a general engineering target.
科研通智能强力驱动
Strongly Powered by AbleSci AI