The living cell is controlled by a multitude of regulatory mechanisms. In addition to the difficulty of approaching the molecular processes of life, it is this sheer complexity that makes biology one of the most challenging topics for the physical chemist. We are attempting to deal with complexity by reducing it along the lines indicated by the organization of cell physiology itself. With respect to control analysis, this implies that we attempt to discern the parts of the cell that function as units in interactions with other such units in the cell. We have identified such units in covalent cascades of enzymes modifying one another, in the regulation of enzyme concentrations through gene expression, as well as in the processes generating and the processes consuming the proton gradient in oxidative phosphorylation.
KeywordsPermeability Respiration Assimilation Glutamine Cytosol
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