S98: Thermodynamic foundation of evolving metabolic networks

The entropy balance of an open system at steady state demonstrates that the entropy content of such system is directly related to the rate of entropy generation in the system due to process irreversibility.  Thus, a maximization of the system entropy corresponds to a maximization of the rate of entropy generation in the system.  Metabolic networks function according to discrete states represented by elementary flux modes.  The most probable distribution of these states can be described using statistical thermodynamics principles.  Adaptive evolution experiments suggest that metabolic networks evolve towards such distribution of elementary modes.  Knowledge of this distribution permits identification of limiting steps in the network that enables rational metabolic engineering of the network.