[Changes in the properties of hexokinase from hyaloplasm on binding with mitochondria].

It has been found that adenylic nucleotides at physiological concentrations solubilize mitochondrial hexokinase from muscles. The solubilizing effect of ATP is reversible in the presence of Mg2+ ions. It is shown that Mg2+ and glucose induce the transition of isoenzymes I and II of hexokinase from the free state to the bound one. Kinetic parameters of the free and bound forms of hexokinase have been determined. The stability of hexokinase has been found to vary, depending on its localization in the cell. Possible action mechanisms of reagents, exerting solubilizing and binding effects on the enzyme and the physiological role of hexokinase ability to exist in free and bound states are discussed.