Malate dehydrogenase is an enzyme of the citric acid cycle, urea cycle, and glyoxylate cycle catalyzing the reaction below:

L-Malate + NAD⁺ <=> Oxaloacetate + NADH + H⁺  ( = +29.7 kJ/mol)

This highly endergonic reaction proceeds to produce oxaloacetate because the highly exergonic citrate synthase reaction keeps intramitchondrial oxaloacetate levels exceedingly low (below 1uM).

Plants have one form of the enzyme in glyoxysomes and another in mitochondria.

Next enzyme of citric acid cycle / Previous enzyme of cycle

1. Glyoxylate Cycle Metabolism

2. Citric Acid Cycle

3. Urea Cycle and Metabolism of Amino Groups