Kinetic analysis of a general model of activation of aspartic proteinase zymogens.

Grupo de Modelización en Bioquímica, Departamento de Química-Física, Escuela Politécnica Superior de Albacete, Universidad de Castilla-La Mancha, Albacete, Spain.
Journal of Theoretical Biology (Impact Factor: 2.35). 11/2006; 242(3):743-54. DOI:10.1016/j.jtbi.2006.04.013
Source: PubMed

ABSTRACT Starting from a simple general reaction mechanism of activation of aspartic proteinase zymogens involving an uni- and a bimolecular simultaneous route, the time course equation of the concentration of the zymogen and of the activated enzyme have been derived. From these equations, an analysis quantifying the relative contribution to the global process of the two routes has been carried out for the first time. This analysis suggests a way to predict the time course of the relative contribution as well as the effect of the initial zymogen and activating enzyme concentrations, on the relative weight. An experimental design and kinetic data analysis is suggested to estimate the kinetic parameters involved in the reaction mechanism proposed. Finally, we apply some of our results to experimental data obtained by other authors in experimental studies of the activation of some aspartic proteinase zymogens.

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