Tyrosine hydroxylase

• OMIM: 191 290
• UniProt: P07101

Tyrosine hydroxylase ( TYH ) is that the enzyme that catalyzes the conversion of the amino acid L- tyrosine in the amino acid levodopa, the rate-determining step in the biosynthesis reaction of the catecholamines. TYH occurs in multicellular animals. In humans, it is produced in the adrenal glands and brain. Mutations in the TH gene may result in enzyme deficiency and the ( rare ) Segawa syndrome. TYH is an autoantigen in the disease APECED.

Inhibition of TYH done by docking of dopamine in two places on the enzyme. By phosphorylation of a serine residue at one of the docking TYH can be reactivated.

Tyrosine hydroxylase uses tetrahydrobiopterin as a cofactor.

Catalyzed reaction

BH4 O2 BH4 -OH

L- tyrosine is oxidized to L- DOPA.