Sauer 1973 Biochem Biophys Res Commun
|Sauer LA (1973) An NAD- and NADP-dependent malic enzyme with regulatory properties in rat liver and adrenal cortex mitochondrial fractions. Biochem Biophys Res Commun 50:524-31.|
Abstract: The NAD- and NADP-dependent malic enzymes from rat liver and adrenal mitochondrial fractions were separated and partially purified by gel filtration on Sepharose 6B. Two activity peaks were observed. The first contained a malic enzyme capable of reducing either NAD or NADP. This enzyme showed sigmoid kinetics in plots of activity versus the malate concentration. Succinate was an allosteric activator and ATP was a competitive inhibitor of malate. The second peak showed hyperbolic kinetics in plots of activity versus the malate concentration and was unaffected by either succinate or ATP. The relative activities of the two malic enzymes were quite constant in the adrenal mitochondrial fractions. In the liver mitochondrial fractions, the activity of the first peak varied and was sometimes absent while the activity of the second peak was quite constant. The kinetic properties of the first malic enzyme implicate it as an important regulator of malate oxidation.
Organism: Rat Tissue;cell: Nervous system, Liver Preparation: Enzyme