Limitation of Metabolite Concentrations and the Conservation of Solvent Capacity in the Living Cell

Publisher Summary This chapter discusses the limitations of the metabolite concentrations and the conservation of solvent capacity in the living cell. The maintenance of low concentrations of metabolites may well be the most pressing problem of metabolic control. Several features of metabolism and of metabolic enzymes appear to represent adaptations to the need to limit solute concentrations and to conserve solvent capacity. Conservation of low concentrations of metabolites, both individually and collectively, is one of the most fundamental requisites for a viable metabolizing system. If concentrations of intermediates are to be kept low, it is necessary that the Michaelis constant of each enzyme involved in a sequence has an appropriate value and that the activity of each enzyme is high enough to handle the maximal flux through the sequence without the substrate concentration rising much above this Michaelis value. The activation of metabolic intermediates, coordinate derepression, or induction contributes to stability and survival through aiding in the conservation of low concentrations within the cell.