Human Dopamine beta-hydroxylase/DBH, C-His Tag Protein (HA211471)

Dopamine beta-hydroxylase (DBH), also known as dopamine beta-monooxygenase, is an enzyme (EC 1.14.17.1) that in humans is encoded by the DBH gene. Dopamine is converted to norepinephrine by the enzyme dopamine β-hydroxylase; ascorbic acid serves as a cofactor. The three substrates of the enzyme are dopamine, vitamin C (ascorbate), and O2. The products are norepinephrine, dehydroascorbate, and H2O. DBH is a 290 kDa copper-containing oxygenase consisting of four identical subunits, and its activity requires ascorbate as a cofactor. It is the only enzyme involved in the synthesis of small-molecule neurotransmitters that is membrane-bound, making norepinephrine the only known transmitter synthesized inside vesicles. It is expressed in noradrenergic neurons of the central nervous system (i.e. locus coeruleus) and peripheral nervous systems (i.e. sympathetic ganglia), as well as in chromaffin cells of the adrenal medulla.