Reaction: L-tyrosine + tetrahydrobiopterin + O2 = L-dopa + 4a-hydroxytetrahydrobiopterin
For diagram click here and here.
Glossary: L-dopa = 3,4-dihydroxy-L-phenylalanine
Other name(s): L-tyrosine hydroxylase; tyrosine 3-hydroxylase; tyrosine hydroxylase
Systematic name: L-tyrosine,tetrahydrobiopterin:oxygen oxidoreductase (3-hydroxylating)
Comments: The active centre contains mononuclear iron(II). The enzyme is activated by phosphorylation, catalysed by EC 18.104.22.168, [acetyl-CoA caboxylase]kinase. The 4a-hydroxytetrahydrobiopterin formed can dehydrate to 6,7-dihydrobiopterin, both spontaneously and by the action of EC 22.214.171.124, 4a-hydroxytetrahydrobiopterin dehydratase. The 6,7-dihydrobiopterin can be enzymically reduced back to tetrahydrobiopterin, by EC 126.96.36.199 (6,7-dihydropteridine reductase), or slowly rearranges into the more stable compound 7,8-dihydrobiopterin.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9036-22-0
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