2du8
Crystal structure of human D-amino acid oxidaseCrystal structure of human D-amino acid oxidase
Structural highlights
FunctionOXDA_HUMAN Regulates the level of the neuromodulator D-serine in the brain. Has high activity towards D-DOPA and contributes to dopamine synthesis. Could act as a detoxifying agent which removes D-amino acids accumulated during aging. Acts on a variety of D-amino acids with a preference for those having small hydrophobic side chains followed by those bearing polar, aromatic, and basic groups. Does not act on acidic amino acids.[1] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedIn the brain, the extensively studied FAD-dependent enzyme D-amino acid oxidase (DAO) degrades the gliotransmitter D-serine, a potent activator of N-methyl-D-aspartate type glutamate receptors, and evidence suggests that DAO, together with its activator G72 protein, may play a key role in the pathophysiology of schizophrenia. Indeed, its potential clinical importance highlights the need for structural and functional analyses of human DAO. We recently succeeded in purifying human DAO, and found that it weakly binds FAD and shows a significant slower rate of flavin reduction compared with porcine DAO. However, the molecular basis for the different kinetic features remains unclear because the active site of human DAO was considered to be virtually identical to that of porcine DAO, as would be expected from the 85% sequence identity. To address this issue, we determined the crystal structure of human DAO in complex with a competitive inhibitor benzoate, at a resolution of 2.5 Angstrom. The overall dimeric structure of human DAO is similar to porcine DAO, and the catalytic residues are fully conserved at the re-face of the flavin ring. However, at the si-face of the flavin ring, despite the strict sequence identity, a hydrophobic stretch (residues 47-51, VAAGL) exists in a significantly different conformation compared with both of the independently determined porcine DAO-benzoate structures. This suggests that a context-dependent conformational variability of the hydrophobic stretch accounts for the low affinity for FAD as well as the slower rate of flavin reduction, thus highlighting the unique features of the human enzyme. Crystal structure of human D-amino acid oxidase: context-dependent variability of the backbone conformation of the VAAGL hydrophobic stretch located at the si-face of the flavin ring.,Kawazoe T, Tsuge H, Pilone MS, Fukui K Protein Sci. 2006 Dec;15(12):2708-17. Epub 2006 Nov 6. PMID:17088322[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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