D-Aspartate Oxidase (DDO)

D-Aspartate Oxidase is a peroxisomal flavoprotein that catalyzes the oxidative deamination of D-aspartate and N-methyl D-aspartate. Flavin adenine dinucleotide or 6-hydroxyflavin adenine dinucleotide can serve as the cofactor in this reaction. Two transcript variants encoding different isoforms have been found for this gene.

The human DDO1 protein has 86.4% amino acid identity with bovine DDO. DDO1 produces a 37-kD protein that efficiently oxidizes D-aspartate and N-methyl-D-aspartate but not D-glutamate; DDO2 produces an insoluble protein whose functional role could not be determined.Indeed it is the existence of these variants that showed the autosomal inheritance and genetic separateness from D-amino acid oxidase.