malate dehydrogenase

(redirected from malic acid dehydrogenase)
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ma·late de·hy·dro·gen·ase (MD),

an enzyme that, using either NAD+ or NADP+, catalyzes the dehydrogenation of malate to oxaloacetate or its decarboxylation to pyruvate and CO2. At least six malate dehydrogenases are known, distinguished by their products, use of NAD+ or NADP+, and specificity of substrate (one acts on d-malate, the rest act on l-malate); one of these proteins is an enzyme in the tricarboxylic acid cycle.

malate dehydrogenase

An oxidoreductase (EC 1.1.1.37) in mitochondria and the cytosol that catalyses the reversible NAD+/NADH reaction in the presence of S-malate, yielding oxaloacetate, a step in the citric acid cycle. Malate dehydrogenase is increased in myocardial infarction, hepatocellular necrosis, megaloblastic anaemia, and cancer.

mal·ate de·hy·dro·gen·ase

(mal'āt dē-hī'drō-jĕ-nās)
Any enzyme that catalyzes the dehydrogenation of malate to oxaloacetate. At least six are known; one is an enzyme in the tricarboxylic acid cycle.