Predicting the Structural Design of Metabolic Pathways: An Evolutionary Approach

摘要

Metabolic systems are characterized by two different types of data, describing first their structural properties (stoicheiometric relations of the chemical conversions, regulatory couplings, kinetic parameter of the enzymes), and second their variables (metabolite concentrations, fluxes). The former are generally fixed during the life span of a cell or an organism, whereas the latter may change in a short time scale, for example within hours or days. To elucidate the main features of the structural properties of metabolic systems one has to take into account that the various enzyme systems withint he cells are the result of selection. We follow the hypothesis that the stoicheiometric design of metabolism, as well as the kinetic design of enzymatic mechanisms, may be explained in terms of optimization principles (Heinrich & Holzhutter, 1985; Melendez-Hevia & Isidoro, 1985; Heinrich et al., 1991), which also apply to understanding the structure of macromolecules such as glycogen, as Melendez-Hevia describes in Chapter 36. It may be expected that such a theoretical approach is not only of academic interest but will also be useful for the purposeful modification (optimization) of metabolism in biotechnology.