L2500

L-Lactic Dehydrogenase from rabbit muscle

Type II, ammonium sulfate suspension, 800-1,200 units/mg protein

• Synonym(s): Lactate, (S)-Lactate: NAD⁺ oxidoreductase, L-LDH, LAD, LD
• CAS Number: 9001-60-9
• Enzyme Commission number: 1.1.1.27 (BRENDA, IUBMB)
• EC Number: 232-617-8
• MDL number: MFCD00131466
• UNSPSC Code: 12352204
• NACRES: NA.54

Properties

• type: Type II
• form: ammonium sulfate suspension
• specific activity: 800-1,200 units/mg protein
• mol wt: 140 kDa
• foreign activity: pyruvate kinase, myokinase, malic dehydrogenase, glutamic-pyruvic transaminase, glutamic-oxalacetic transaminase and α-glycerophosphate dehydrogenase ≤0.01%
• shipped in: wet ice
• storage temp.: 2-8°C

Description

General description

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 dissociates into dimeric species (MW = ~70 kDa) in acetate-chloride at pH 5.0, the dissociation is reversible. Biochemistry, 13, 3527-3531 (1974). Oxidizes glyoxylate and lactate.
Isoelectric point: 8.4-8.6
Optimal pH : 7.5 .

Application

L-Lactic Dehydrogenase from rabbit muscle has been used:

• for protein-binding measurement
• to detect the action of oxaloacetate decarboxylase
• to determine serum L- and D-lactate

Biochem/physiol Actions

Lactic dehydrogenase is responsible for the conversion of pyruvate to lactate in the fermentative metabolism.

Also catalyzes the oxidation of other L-2-hydroxymonocarboxylic acids.

Unit Definition

One unit will reduce 1.0 μmole of pyruvate to L-lactate per min at pH 7.5 at 37 °C.

Physical form

Crystalline suspension in 3.2 M (NH₄)₂SO₄ solution, pH 6.0

Analysis Note

Protein determined by biuret.

Safety Information

• Pictograms: GHS08
• Signal Word: Danger
• Hazard Statements: H334
• Precautionary Statements: P261 - P284 - P501
• Hazard Classifications: Resp. Sens. 1
• Storage Class Code: 10 - Combustible liquids
• WGK: WGK 1
• Personal Protective Equipment: dust mask type N95 (US), Eyeshields, Gloves