Amino Acid Oxidase, D-
D-amino acid oxidase is a flavoprotein. D-amino acid oxidase derived from porcine liver has been extensively studied. The enzyme is isolated as a stable crystalline complex with benzoate, from which the holo- and apoenzyme may be prepared. The benzoate is readily exchanged for a substrate. D-amino acid oxidase in the presence of molecular oxygen oxidatively deaminates D-amino acides to corresponding α-keto-acids:
Stability/Storage: The enzyme is stable for months at 2-8°C as a dry, lyophilized powder and in solution at high protein concentration at 2-8°C. 1.4 x 10-5 M FAD prevents loss of activity upon dilution (Dixon and Kleppe, Biochim. Biophys. Acta, 96, 368, 1965).
1 Unit oxidizes 1 µmole of D-alanine per minute at 37°C, pH 8.3.