Malate dehydrogenase

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Malate dehydrogenase
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Malate dehydrogenase
malate dehydrogenase 1, NAD (soluble)
Identifiers
Symbol(s) MDH1
Entrez 4190
OMIM 154200
RefSeq NM_005917
UniProt P40925
Other data
EC number 1.1.1.37
Locus Chr. 2 p23
malate dehydrogenase 2, NAD (mitochondrial)
Identifiers
Symbol(s) MDH2
Entrez 4191
OMIM 154100
RefSeq NM_005918
UniProt P40926
Other data
EC number 1.1.1.37
Locus Chr. 7 cen-q22

Malate dehydrogenase (EC 1.1.1.37) is an enzyme in the citric acid cycle that catalyzes the conversion of malate into oxaloacetate (using NAD+) and vice versa (this is a reversible reaction). Malate dehydrogenase is not to be confused with malic enzyme, which catalyzes the conversion of pyruvate using NADPH.

Malate dehydrogenase is also involved in gluconeogenesis, the synthesis of glucose from smaller molecules. Pyruvate in the mitochondria is acted upon by pyruvate carboxylase to form oxalocacetate, a citric acid cycle intermediate. In order to get the oxaloacetate out of the mitochondria, malate dehydrogenase reduces it to malate, and it then traverses the inner mitochondrial membrane. Once in the cytosol, the malate is oxidized back to oxaloacetate by cytosolic malate dehydrogenase. Finally, phosphoenol-pyruvate carboxy kinase (PEPCK) converts oxaloacetate to phosphoenol pyruvate.

The Cas number for this type of the enzyme is [9001-64-3].

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