Galactose oxidase

galactose oxidase
Identifiers
EC number	1.1.3.9
CAS number	9028-79-9
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Gene Ontology	AmiGO / EGO
Search PMC articles PubMed articles

In enzymology, a galactose oxidase (EC 1.1.3.9) is an enzyme that catalyzes the chemical reaction

D-galactose + O₂ $\rightleftharpoons$ D-galacto-hexodialdose + H₂O₂

Thus, the two substrates of this enzyme are D-galactose and O₂, whereas its two products are D-galacto-hexodialdose and H₂O₂.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with oxygen as acceptor. The systematic name of this enzyme class is D-galactose:oxygen 6-oxidoreductase. Other names in common use include D-galactose oxidase, and beta-galactose oxidase. It employs two cofactors, copper and an active site amino acid derived post-translational modification involving the covalent cross-linking of Cys228 and Tyr272 and which represents the site of the catalytic free radical.

Structural studies

As of late 2007, 9 structures have been solved for this class of enzymes, with PDB accession codes 1GOF, 1GOG, 1GOH, 1K3I, 1T2X, 2EIB, 2EIC, 2EID, and 2EIE.

References

• AVIGAD G, AMARAL D, ASENSIO C, HORECKER BL (1962). "The D-galactose oxidase of Polyporus circinatus". J. Biol. Chem. 237: 2736–43. PMID 13863403.