InterPro domain: IPR034282

CopA is a multicopper oxidase (MCO) related to laccase and L-ascorbate oxidase, both copper-containing enzymes [ 1 , 2 ]. CopA mutant causes a loss of function including copper tolerance and oxidase activity and copA transcription is inducible in the presence of copper [ 3 ].

Although MCOs have diverse functions, majority of them have three cupredoxin domain repeats that include one mononuclear and one trinuclear copper centre. The copper ions are bound in several sites: Type 1, Type 2, and/or Type 3. The ensemble of types 2 and 3 copper is called a trinuclear cluster. MCOs oxidize their substrate by accepting electrons at a mononuclear copper centre and transferring them to the active site trinuclear copper centre. The cupredoxin domain 2 of 3-domain MCOs has lost the ability to bind copper [ 4 , 5 , 6 , 7 ].

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2. Copper resistance in E. coli: the multicopper oxidase PcoA catalyzes oxidation of copper(I) in Cu(I)Cu(II)-PcoC. null , 1579-82
3. Functional characterization of copA gene encoding multicopper oxidase in Xanthomonas campestris pv. campestris. Chembiochem 9, 9290-302
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6. A structure-derived sequence pattern for the detection of type I copper binding domains in distantly related proteins. FEBS Lett. 279, 73-8
7. Refined crystal structure of ascorbate oxidase at 1.9 A resolution. J. Mol. Biol. 224, 179-205