Protein Domain : Multicopper oxidase, copper-binding site IPR002355

Type	Binding_site
Description	The entry represents a conserved region containing the Cu-binding site found in multicopper oxidases. Multicopper oxidases oxidise their substrate by accepting electrons at a mononuclear copper centre and transferring them to a trinuclear copper centre; dioxygen binds to the trinuclear centre and, following the transfer of four electrons, is reduced to two molecules of water [ ]. There are three spectroscopically different copper centres found in multicopper oxidases: type 1 (or blue), type 2 (or normal) and type 3 (or coupled binuclear) [, ]. Multicopper oxidases consist of 2, 3 or 6 of these homologous domains, which also share homology to the cupredoxins azurin and plastocyanin. Structurally, these domains consist of a cupredoxin-like fold, a β-sandwich consisting of 7 strands in 2 β-sheets, arranged in a Greek-key β-barrel []. Multicopper oxidases include:Ceruloplasmin ( ) (ferroxidase), a 6-domain enzyme found in the serum of mammals and birds that oxidizes different inorganic and organic substances; exhibits internal sequence homology that appears to have evolved from the triplication of a Cu-binding domain similar to that of laccase and ascorbate oxidase. Laccase ( ) (urishiol oxidase), a 3-domain enzyme found in fungi and plants, which oxidizes different phenols and diamines. CueO is a laccase found in Escherichia coli that is involved in copper-resistance [ ].Ascorbate oxidase ( ), a 3-domain enzyme found in higher plants. Nitrite reductase ( ), a 2-domain enzyme containing type-1 and type-2 copper centres [ , ].
Short Name	Cu_oxidase_Cu_BS