Structural and functional characterization of the human brain D-aspartate oxidase.
D-Aspartate oxidase (DDO) cDNAs were isolated from the human brain RNA using the RT-PCR method. Two forms (DDO-1 and DDO-2) of DDO mRNA were detected. Structural analysis of the DDO cDNAs and genomic DNA showed that DDO-1 and DDO-2 are produced by alternative splicing from a single gene. A protein encoded by the DDO-1 cDNA consists of 341 amino acids, and the amino acid sequence of DDO-2 was identical to that of DDO-1 except for the absence of 59 amino acids covering residues 95-153 of DDO-1. A homogenous preparation of DDO-1 was obtained using an expression system in Escherichia coli. DDO-1 selectively catalyzed the oxidative deamination of D-aspartate and its N-methylated derivative, N-methyl D-aspartate; the values of K(m) and k(cat) for D-aspartate were 2.7 mM and 52.5 mol D-aspartate oxidized x s(-1) x mol(-1) and those for N-methyl D-aspartate were 6.8 mM and 37.7 mol N-methyl D-aspartate oxidized x s(-1) x mol(-1), respectively.
Setoyama
C
C
Department of Biochemistry, Kumamoto University School of Medicine, Honjo.
Miura
R
R
D000594:Amino Acid Oxidoreductases / Q000235:genetics* / Q000378:metabolism*; D000595:Amino Acid Sequence; D001483:Base Sequence; D001921:Brain / Q000201:enzymology*; D003001:Cloning, Molecular; D050804:D-Aspartate Oxidase; D018076:DNA, Complementary / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics; D006801:Humans; D007527:Isoenzymes; D007700:Kinetics; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity
D018076:DNA, Complementary; D007527:Isoenzymes; D011994:Recombinant Proteins; D000594:Amino Acid Oxidoreductases; D050804:D-Aspartate Oxidase; C494102:DDO protein, human