L-Lactate Dehydrogenase (L-LDH)
from pig muscle, for use of AST/GOT-Determination according to IFCC recommendations, solution
For further processing only.
L-Lactate Dehydrogenase (L-LDH) material number and pack size: Material Number Pack Size 10417718103 custom fill
- Dehydrogenase that catalyzes the interconversion of specific for L(+)-lactate to pyruvate.
- Use L-Lactate Dehydrogenase in a in a variety of diagnostic tests for the removal of pyruvate in determinations working with NADH (i.e., triglycerides, lipase, aldolase, aminotransferases, glutamate dehydrogenase).
Nomenclature: L-lactate:NAD+ oxidoreductase
Molecular weight: 140 kD
Isoelectric point: 4.6
Michaelis constants (Phosphate buffer, pH 7.5; +25°C):
Pyruvate: 1.5 x 10-4 mol/L (NADH: 0.18 mmol/L)
L-lactate: 3.3 x 10-3 mol/L (NAD: 0.5 mmol/L)
NADH: 1.1 x 10-5 mol/L (Pyruvate: 0.6 mmol/L)
NAD: 6.7 x 10-5 mol/L (L-lactate: 34 mmol/L)
Inhibitors: Oxamate, pyruvate (excess), oxalate, Ag+, Hg2+, Cu2+
pH optimum: 3.0-7.0 (see figure for product Cat. No. 10 254 754 103)
Temperature dependence: See figure for product Cat. No. 10 254 754 103
pH stability: 5.5-8.5 (see figure for product Cat. No. 10 254 754 103)
Thermal stability: Up to +40°C (see figure for product Cat. No. 10 254 754 103)
Specificity: Lactate dehydrogenase is specific for L(+)-lactate, D(-)-lactate does not react. Glyoxylate is also a lactate dehydrogenase substrate. Apart from pyruvate some 2-oxoacids are reduced. NAD analogs (e.g., APAD) react at similar rates. Appearance: Clear, colorless solution in glycerol, 50% (v/v), pH approximately 7
pH value: 6.5-7.5
Activity (+30°C, pyruvate, according to the IFCC recommendations): ≥9,600 U/mL solution
Specific activity: ≥480 U/mg protein
Protein (Biuret): ≥20 mg/mL solution
Glycerol: 560-680 mg/L ≙ 45-55 % (v/v)
Contaminants (expressed as percentage of Lactate Dehydrogenase specific activity):
Glutamate dehydrogenase: ≤0.003
Aspartate aminotransferase (AST/GOT): ≤0.005
Alanine aminotransferase (ALT/GPT): ≤0.005
Reagent blank for determination of aspartate aminotransferase (AST/GOT): ≤0.9 mA/min
SVD free: Corresponds to specification
pH 5.5 treatment (30 minutes): Corresponds to specification
Stability: At +2 to +8°C within specification range for 12 months.