?
Eukaryotic phenylalanine-4-hydroxylase (eu_PheOH); a member of the biopterin-dependent aromatic amino acid hydroxylase family of non-heme, iron(II)-dependent enzymes that also includes prokaryotic phenylalanine-4-hydroxylase (pro_PheOH), eukaryotic tyrosine hydroxylase (TyrOH) and eukaryotic tryptophan hydroxylase (TrpOH). PheOH catalyzes the first and rate-limiting step in the metabolism of the amino acid L-phenylalanine (L-Phe), the hydroxylation of L-Phe to L-tyrosine (L-Tyr). It uses (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin (BH4) as the physiological electron donor. The catalytic activity of the tetrameric enzyme is tightly regulated by the binding of L-Phe and BH4 as well as by phosphorylation. Mutations in the human enzyme are linked to a severe variant of phenylketonuria.
|
Jiyao W et al.(2023). "The conserved domain database in 2023.",