Blue copper proteins oxygen activation

Copper-containing amine oxidases (non-blue copper proteins) catalyze the oxidative deamination of primary amines to the corresponding aldehydes with the release of ammonia and concomitant reduction of oxygen to hydrogen peroxide. They typically use a quinone redox cofactor [topaquinone (TPQ)], which is bound covalently in the active site, and are thought to form a Cu(I)-TPQ semi-quinone radical intermediate during the redox reaction [13]. 

Both hemocyanin and tyrosinase, the enzyme that activates molecular oxygen for the oxidation of tyrosine, rely on direct covalent interaction between Cu(I) and O2, forming an observable dioxygen adduct. The mushroom Gyroporus cyanescens (Bluing Boletus), which turns blue instantly when bruised, also contains a copper protein or a blue protein, as it is called. 

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