Cat No.
DIA-160
Description
Malate dehydrogenase 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 malate to pyruvate producing 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 oxaloacetate, 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.
Abbr
MDH (Microorganism)
Alias
NAD-sp; MDH
Species
Microorganism
Form
Freeze dried powder
Enzyme Commission Number
EC 1.1.1.37
Bio-activity
GradeⅡ 40U/mg-solid or more
Appearance
Slightly yellowish amorphous powder, lyophilized
Molecular Mass
approx. 140 kDa
pH Stability
pH 3.0-9.0 (25°C, 20hr)
Michaelis Constant
5.4×10??M (L-Malate), 5.0×10??M (Oxaloacetate), 8.1×10??M (NADH)
Structure
4 subunits per mole of enzyme
Isoelectric point
pH 4.8±0.1
Optimum pH
8
Optimum temperature
70°C
Thermal stability
below 70°C (pH 7.5, 15min)
Stability
Stable at-20°C for at least one year
Inhibitors
Hg??
Applications
This enzyme is useful for enzymatic determination of L-malate and of glutamate oxaloacetate transaminase (GOT) in clinical analysis.
Synonyms
malic dehydrogenase; L-malate dehydrogenase; NAD-L-malate dehydrogenase; malic acid dehydrogenase; NAD-dependent malic dehydrogenase; NAD-malate dehydrogenase; NAD-malic dehydrogenase; malate NAD dehydrogenase; NAD-dependent malate dehydrogenase; NAD-sp; ECific malate dehydrogenase; NAD-linked malate dehydrogenase; MDH; L-malate-NAD+ oxidoreductase; S-malate: NAD+ oxidoreductase; EC 1.1.1.37; Malate Dehydrogenase
