<unk>  or<unk>  3-monooxygenase is<unk> e enzyme responsible for catalyzing<unk> e conversion of<unk> e amino acid L-tyrosine to L-3,4-dihydroxyphenylalanine (L-DOPA). It does so using molecular oxygen (O2), as well as iron (Fe2+) and tetrahydrobiopterin as cofactors. L-DOPA is a precursor for dopamine, which, in turn, is a precursor for<unk> e important neurotransmitters norepinephrine (noradrenaline) and epinephrine (adrenaline).<unk>  catalyzes<unk> e rate limiting step in<unk> is synthesis of catecholamines. In humans,<unk>  is encoded by<unk> e<unk>  gene, and<unk> e enzyme is present in<unk> e central nervous system (CNS), peripheral sympathetic neurons and<unk> e adrenal medulla.<unk> , phenylalanine<unk>  and tryptophan<unk>  together make up<unk> e family of aromatic amino acid<unk> s (AAAHs).
Tyrosine hydroxylase
Dopamine beta-hydroxylase
Phenylalanine hydroxylase
Catechol-O-methyltransferase
Aromatic L-amino acid decarboxylase
Monoamine oxidase
Glutamate dehydrogenase
Monoamine oxidase B