Consideration of the gain, enzymatic capacity utilization, and response time properties of metabolic networks as a...

Computer simulation is used to examine the gain, utilization of enzymatic capacity and response time properties of a simple metabolic network consisting of a sequence of irreversible enzyme reactions controlled by non-allosteric feedback inhibition. The latter properties are chosen because interpretation of a metabolic network's structure can be aided by envisioning the network to maximize a single objective such as flux control. However, by examining the properties as a function of the network's operating point (extent of saturation of the first enzymatic reaction) and structural characteristics, it is found that apparent trade-offs occur between definable objectives. It is suggested that greater consideration of the trade-offs that may occur could help generate metabolic network heuristics and facilitate the interpretation of metabolic networks in terms of the functional role they play in the intact organism.