[Kinetic and regulatory properties of reversible enzymic reactions]

The model of a reversible reaction catalyzed by an oligomeric enzyme has been investigated. The regions of parameter values have been estimated at which the model describes "unidirectional" or alternative effects of allosteric modifiers on the rates of forward and backward reactions. The plausible explanation and mathematical description are offered for kinetic and regulatory peculiarities of reversible reactions catalyzed by NAD-dependent isocitrate dehydrogenase and catabolic ornithine carbamoylphosphate transferase. The phenomena of unidirectional catalysis of alternative directions of a reversible reaction by different enzymes are considered.