Reaction: an N-(1-deoxy-D-fructos-1-yl)amine + O2 + H2O = D-glucosone + an amine + H2O2 (overall reaction)
(1a) an N-(1-deoxy-D-fructos-1-yl)amine + O2 = a 2-[(3S,4R,5R)-3,4,5,6-tetrahydroxy-2-oxohexylidene]amine + H2O2
(1b) a 2-[(3S,4R,5R)-3,4,5,6-tetrahydroxy-2-oxohexylidene]amine + H2O = D-glucosone + an amine (spontaneous)
Other name(s): amadoriase
Systematic name: N-(1-deoxy-D-fructos-1-yl)amine:oxygen 2-oxidoreductase (glucosone-forming)
Comments: Reducing sugars such as glucose react with amino groups in proteins via the spontaeous Maillard reaction, forming an unstable product that undergoes spontaneous rearrangement to a keto amine compound. These reactions are known as glycation reactions, and the stable products are known as Amadori products. This enzyme, which contains an FAD cofactor, catalyses a deglycation reaction that regenerates the amine reactant. By-products are glucosone and hydrogen peroxide. The enzymes have been reported from fungi and bacteria, but not from higher eukaryotes. Specific enzymes differ in their substrate specificity. cf. EC 1.5.3.26, fructosyl amine oxidase (fructosamine-forming).
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Horiuchi, T., Kurokawa, T. and Saito, N. Purification and properties of fructosyl-amino acid oxidase from Corynebacterium sp. 2-4-1. Agr Biol Chem Tokyo 53 (1989) 103-110.
2. Takahashi, M., Pischetsrieder, M. and Monnier, V.M. Molecular cloning and expression of amadoriase isoenzyme (fructosyl amine:oxygen oxidoreductase, EC 1.5.3) from Aspergillus fumigatus. J. Biol. Chem. 272 (1997) 12505-12507. [PMID: 9139700]
3. Hirokawa, K. and Kajiyama, N. Recombinant agrobacterium AgaE-like protein with fructosyl amino acid oxidase activity. Biosci. Biotechnol. Biochem. 66 (2002) 2323-2329. [PMID: 12506967]
4. Wu, X. and Monnier, V.M. Enzymatic deglycation of proteins. Arch. Biochem. Biophys. 419 (2003) 16-24. [PMID: 14568004]
5. Sakaue, R., Nakatsu, T., Yamaguchi, Y., Kato, H. and Kajiyama, N. Crystallization and preliminary crystallographic analysis of bacterial fructosyl amino acid oxidase. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 61 (2005) 196-198. [PMID: 16510992]