A lactate dehydrogenase (LDH or LD) is an enzyme found in nearly all living cells (animals, plants, and prokaryotes). LDH catalyzes the conversion of pyruvate to lactate and back, as it converts NADH to NAD+ and back. A dehydrogenase is an enzyme that transfers a hydride from one molecule to another.
L-LDH, Native (Rabbit)
Lactic Dehydrogenase (LDH) has a total molecular weight of 140 kDa and is composed of 4 subunits which are designated M subunit (muscle) and H subunit (heart). These subunits may be mixed in any of 5 combinations (M4, M3H1, M2H2, MH3, and H4). Skeletal muscle contains LDH that is predominately M4 with some small amounts of M3H and traces of H2H2. The H and M subunits are quite similar in molecular weight, but differ substantially in amino acid composition. Rabbit muscle LDH diss ociates into dimeric species (MW = ~70 kDa) in acetate-chloride at pH 5.0, the diss ociation is reversible. Bi ochemistry, 13, 3527-3531 (1974). Oxidizes glyoxylate and lactate.
Type I, lyophilized powder; Type II, ; Type III, ammonium sulfate suspension, Crystalline suspension in 3.2 M (NH4)2SO4 solution, pH 6.0.
Enzyme Commission Number
One unit will reduce 1.0 μmole of pyruvate to L-lactate per min at pH 7.5 at 37°C.
Protein determined by biuret.
EC 18.104.22.168; 9001-60-9; lactic acid dehydrogenase; L (+)-nLDH; L-(+)-lactate dehydrogenase; L-lactic dehydrogenase; L-lactic acid dehydrogenase; lactate dehydrogenase; lactate dehydrogenase NAD-dependent; lactic dehydrogenase; NAD-lactate dehydrogenase; L-lactate dehydrogenase; (S)-Lactate:NAD+ oxidoreductase; L-LDH; LAD; LD; Lactate