Wu J W, Wu Y, Wang Z X
National Laboratory of Biomacromolecules, Institute of Biophysics, Academia Sinica, Beijing, China.
Eur J Biochem. 2001 Mar;268(6):1547-53.
Proteolytic enzymes are usually biosynthesized as somewhat larger inactive precursors known as zymogens. These zymogens must undergo an activation process, usually a limited proteolysis, to attain their catalytic activity. When the activating enzyme and the activated enzyme coincide, the process is an autocatalytic zymogen activation. In the present study, a kinetic analysis of the entire progress curve for the autocatalytic zymogen activation reactions is presented. On the basis of the kinetic equations, a novel procedure is developed to evaluate the kinetic parameters of the reactions. This procedure is particularly useful for the fast zymogen autoactivation reactions. As two examples, the novel procedure is used to analyse the autocatalytic activation of bovine trypsinogen and human blood coagulation factor XII (Hageman factor).
蛋白水解酶通常以稍大的无活性前体形式生物合成，这些前体被称为酶原。这些酶原必须经历一个激活过程，通常是有限的蛋白水解，以获得其催化活性。当激活酶和被激活的酶相同时，该过程就是自催化酶原激活。在本研究中，对自催化酶原激活反应的整个进程曲线进行了动力学分析。基于动力学方程，开发了一种新的程序来评估反应的动力学参数。该程序对于快速的酶原自激活反应特别有用。作为两个例子，该新程序被用于分析牛胰蛋白酶原和人凝血因子XII（哈格曼因子）的自催化激活。
