Conversion of dopamine to noradrenaline. dopamine + 2 L-ascorbate + O2 = (R)-noradrenaline + H2O + 2 monodehydro-L-ascorbate radical Binds 2 copper ions per subunit. Catecholamine biosynthesis; (R)-noradrenaline biosynthesis; (R)-noradrenaline from dopamine: step 1/1. Homotetramer; composed of two disulfide-linked dimers. Chromaffin granules of the adrenal medulla and synaptic vesicles of the sympathetic nervous system. Proteolytic cleavage after the membrane-anchor leads to the release of the soluble form. N-glycosylated. Belongs to the copper type II ascorbate-dependent monooxygenase family.