The role of conformational flexibility of enzymes in the discrimination between amino acid and ester substrates for the subtilisin-catalyzed reaction in organic solvents
作者:Keiichi Watanabe、Takashi Yoshida、Shin-ichi Ueji
DOI:10.1016/j.bioorg.2004.05.001
日期:2004.12
substrates for the subtilisin-catalyzed reaction in an organic solvent, the flexibility around the active site and the surface of subtilisin was estimated from the mobility of a spin label bound to subtilisin by ESR spectroscopy. Many studies on enzyme flexibility focus on the active site. Both the surface and active site flexibility play an important role in the enantioselectivity enhancement of the enzyme-catalyzed
为了研究枯草杆菌蛋白酶的构象柔韧性如何影响其区分在有机溶剂中枯草杆菌蛋白酶催化反应的对映体氨基酸和酯底物的能力,通过旋转的迁移率估算了活性中心和枯草杆菌蛋白酶表面的柔韧性ESR光谱法将与枯草杆菌蛋白酶结合的标记。关于酶柔韧性的许多研究都集中在活性位点上。表面和活性位点的柔韧性在酶催化反应的对映选择性增强中都起着重要作用。然而,发现在氨基酸和酯底物之间观察到的对映选择性的不同行为可能与表面周围的柔韧性而不是枯草杆菌蛋白酶活性位点的柔韧性有关。换一种说法,对于酯底物,由于存在添加剂如DMSO而引起的构象变化引起的枯草杆菌蛋白酶表面周围更大的柔韧性对于增强对映选择性是必不可少的。每个对映体底物的Michaelis-Menten动力学参数也支持该模型。我们的发现为有机溶剂中酶催化反应的对映异构体拆分提供了深入的对映选择性的见解。