Principles of optimal metabolic network operation

Abstract

Mol Syst Biol. 3: 126 What is the optimal operation of metabolic networks? This question is interesting to answer, as it would provide information on which underlying principles have shaped metabolic networks during evolution, and it may allow us to identify some simple rules governing the operation of metabolic networks under different growth conditions. Such rules might be important for metabolic network engineering—for example when designing better microbes for the production of fuels, chemicals and materials—but also for the identification of the regulatory mechanisms that ensure the different operations of metabolism. Using reconstructed genome‐scale metabolic models, the group of Palsson has shown on several occasions that a well suited guiding principle—the so‐called ‘objective function’ in the terminology used in metabolic flux balance analysis—for operation of metabolic networks is optimization of growth (Price et al , 2004). In other words, through evolution, microorganisms have evolved in such a way that their metabolic networks ensure the most efficient conversion of carbon and energy to produce more cells. This principle seems to be robust as it was elegantly illustrated in a study where the group looked at growth of the bacterium Escherichia coli …