tailieunhanh - Báo cáo khoa học: Kinetic analysis of zymogen autoactivation in the presence of a reversible inhibitor

Limited proteolysis is a highly specific irreversible process, which can serve to initiate physiological function by con-verting a precursor protein into a biologically active form. When the activating enzyme and the activated enzyme coincide, the process is an autocatalytic zymogen activation (. reactions inwhich the zymogens serves as a substrate for the corresponding active enzyme). The activity of proteases is frequently regulated by the binding of specific protease inhibitors. | Eur. J. Biochem. 271 4638-4645 2004 FEBS 2004 doi Kinetic analysis of zymogen autoactivation in the presence of a reversible inhibitor Wei-Ning Wang Xian-Ming Pan and Zhi-Xin Wang National Laboratory of Biomacromolecules Institute of Biophysics Academia Sinica Beijing . China Limited proteolysis is a highly specific irreversible process which can serve to initiate physiological function by converting a precursor protein into a biologically active form. When the activating enzyme and the activated enzyme coincide the process is an autocatalytic zymogen activation . reactions in which the zymogens serves as a substrate for the corresponding active enzyme . The activity of proteases is frequently regulated by the binding of specific protease inhibitors. Thus to understand the biological regulation of proteolysis one must understand the role of protease inhibitors. In the present study a detailed kinetic analysis of autocatalytic reaction modulated by a reversible inhibitor is represented. On the basis of the kinetic equation a novel procedure is developed to evaluate the kinetic parameters of the reaction. As an example of the application of this method effects of acetamidine p-amidinobenzamidine and benzamidine on the autoactivation of trypsinogen by trypsin were studied. Keywords limited proteolysis reversible inhibition trypsin trypsinogen zymogen activation. Proteolysis is required for a multitude of developmental and physiologic events including digestion metabolism differentiation immunity blood coagulation fibrinolysis apoptosis and response to injury 1-9 . The enzymes responsible for the catalysis of proteolysis are proteases. During the last century the number of known enzymes that demonstrate proteolytic activity has increases exponentially and we have an increased understanding of the mechanisms and critical roles that proteases play in physiological and pathological processes. Proteases are normally biosynthesized as

• Báo cáo khoa học
• Report medicine
• traditional medicine
• scientific reports
• gastric cancer
• hormone medicine
• tumor cells