Glutamate Dehydrogenase (NAD(P))
from beef liver, chemically modified, lyophilizate
For further processing only.
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Glutamate Dehydrogenase (NAD(P)) material number and pack size: Material Number Pack Size 11434993103 custom fill
- Dehydrogenase that catalyzes the conversion of glutamate to α-ketoglutarate.
- Use modified Glutamate Dehydrogenase in diagnostic tests for the determination of ammonia, urea, L-glutamate, glutamate pyruvate transaminase and leucine aminopeptidase.
Nomenclature: L-glutamate:NAD(P)+ oxidoreductase (deaminating)
Molecular weight: ~2 200 kD for the associated enzyme with 8 subunits; 280 kD for one subunit.
Michaelis constants (Tris buffer, pH 8.0, +23°C):
L-glutamate: 1.8 x 10-3 mol/L
NADP: 4.7 x 10-5 mol/L
α-ketoglutarate: 7.0 x 10-4 mol/L
NH4+: 3.2 x 10-3 mol/L
NADPH: 2.6 x 10-5 mol/L
Km values for NAD or NADH are difficult to obtain due to their inhibitory action.
Inhibitors: 4-chloromercuribenzoate, Na2S, diethyldithiocarbamate, 1,10-phenanthroline,
8-hydroxyquinoline, NaN3, thyroxine, heparin, sulfonylcarbamides, Cu2+, Hg2+, Ag2+, Fe3+, Zn2+, K+, PO42-, NO3-
Activators: Thioglycolic acid, b-mercaptoethylamine, EDTA, α, α'-dipyridyl
pH optimum: 8.0 (see figure for product Cat. No. 10 190 462 103)
Temperature dependence: See figure for product Cat. No. 10 190 462 103
pH stability: 5.5-6.5 (see figure for product Cat. No. 10 190 462 103)
Thermal stability: Up to +60°C (see figure for product Cat. No. 10 190 462 103)
Specificity: The oxidation of L-glutamate is stimulated by ADP and inhibited by GTP. In contrast, the oxidation of alanine, leucine, isoleucine, methionine, valine, norleucine, norvaline and 2-aminobutyrates is stimulated by GTP and inhibited by ADP.
- Glutamate dehydrogenase suspension or solution can be dialyzed against phosphate buffer, 10 mmol/L. Glutamate dehydrogenase molecules have the tendency to associate in some test formulations, modified Glutamate dehydrogenase minimizes this effect.
-The modified enzyme is especially suited for liquid stable applications with extended shelf life requirements. Appearance: White lyophilizate, stabilized with RPLA 4 and ADP
Solubility: Clear, slightly opalescent solution in water (c=40 mg/mL)
Activity (+25°C, α-oxoglutarat): ≥7 U/mg lyophilizate
Contaminants (expressed as percentage of Glutamate Dehydrogenase activity):
Alcohol dehydrogenase: ≤0.005
Lactate dehydrogenase: ≤0.005
Malate dehydrogenase: ≤0.005
NH4: ≤0.16 μmol/KU GIutamate Dehydrogenase
K (flame photometric): ≤0.1 μmol/KU Glutamate Dehydrogenase
Na (flame photometric): ≤2.0 μmol/KU Glutamate Dehydrogenase
pH 5.5 treatment (30 minutes): Corresponds to specification
Stability: At +2 to +8°C within specification range for 18 months. Store dry.