[Kinetic and regulatory properties of alpha-ketoglutarate dehydrogenase complex from bovine adrenals]

The dependence of the rate of reactions catalyzed by the alpha-ketoglutarate dehydrogenase complex on the alpha-ketoglutarate, CoA and NAD+ concentration is described by Michaelis-Menten equation. Km is 0.190, 0.012 and 0.025 mM, respectively. ADP plays a role of a complex activator at low alpha-ketoglutarate concentrations. ATP, on the contrary, produces a mixed type inhibition on the alpha-ketoglutarate dehydrogenase complex with respect to CoA and NAD+. A conclusion is drawn that the adrenal alpha-ketoglutarate complex regulation by ATP/ADP ratio value is possible.