Description
ApplicationThis enzyme is useful for enzymatic determination of NH3, α-ketoglutaric acid and L-glutamic acid, and for assay of leucine aminopeptidase and urease. This enzyme is also used for enzymatic determination of urea when coupled with urease (URH-201) in clinical analysis. In vitro, various activity assays of this enzyme examine the conversion of α-ketoglutarate to L-glutamate, in the presence of excess ammonium ions (NH4+) and NADPH.physical propertyIsoelectric point : 4.6Michaelis constants : 1.1 X 10-3M (NH3), 3.4 X 10-4M (α-Ketoglutarate)1.2 X 10-3M (L-Glutamate), 1.4 X 10-5M (NADPH), 1.5 X 10-5M (NADP+)Structure : 6 subunits (M.W.50,000) per mol of enzymeInhibitors : Hg++, Cd++, p-chloromercuribenzoate, pyridine, 4-4′-dithiopyridine,2,2′-dithiopyridineOptimum pH : 8.5 (α-KG→L-Glu) 9.8 (L-Glu→α-KG)Optimum temperature : 45oC(α-KG−L-Glu) 45-55oC (L-Glu→α-KG)pH stability : pH 6.0 - 8.5 (25oC, 20hr)Thermal stability : below 50oC (pH 7.4, 10min)