平面阴离子对肌酸激酶活性的抑制动力学研究

本文将邹氏不可逆改变动力学理论与方法运用于平面阴离子对双底物的肌酸激酶的慢可逆抑制作用的研究中,根据理论分析和实验结果,推导并简化了动力学方程,定量地测定了抑制作用的微观动力学常数,探讨了平面阴离子对肌酸激酶的抑制作用机制。     

Kinetics of the Inactivation of Creatine Kinase During Inhibition by Planar Anions

The kinetic theory of the substrate reaction during the modification of enzyme activity previously described by Tsou has been applied to a study on the kinetics of slow irreversible inhibition of creatine kinase by planar anions. Kinetic equation of substrate reaction was derived according to the theoretical analysis and experiment data, and then was simplified. From the simplified equation for the substrate reaction in the presence of the inhibitors, the microscopic rate constants for the reaction of the inhibitors with enzyme were obtained. The mechanism of inhibition of enzyme activity was discussed.     

氧化型肌酸激酶的研究

利用NR/R双向对角线SDS-PAGE作者首次将过去被认为均一的兔肌肌酸激酶分离为含有链内二硫键的和不含任何二硫键的两种肌酸激酶(前者称为“氧化型肌酸激酶”,后者称为“还原型肌酸激酶”)。它们具有相同的化学组成,相同的亚基分子量,相同的等电点及几乎相同的催化活性,因此用一般常用的分离纯化手段很难将它们分离开来。进一步的研究表明,氧化型的肌酸激酶也含有一对表面巯基,并对酶的活性同样是必需的。氧化型肌酸激酶分子中,每一个亚基含有一个链内二硫键,在没有变性的条件下,不能被DTT还原,而还原型肌酸激酶通过某些氧化剂氧化可以形成这个二硫键,因此作者认为该二硫键可能是由内埋较浅的一对巯基氧化而成的。