CATH Classification

Domain Context

CATH Clusters

Superfamily Aromatic amino acid hydroxylase
Functional Family

Enzyme Information

1.14.16.1
Phenylalanine 4-monooxygenase.
based on mapping to UniProt P00439
L-phenylalanine + tetrahydrobiopterin + O(2) = L-tyrosine + 4a-hydroxytetrahydrobiopterin.
-!- The reaction involves an arene oxide which rearranges to give the phenolic hydroxy group. -!- This results in the hydrogen at C-4 migrating to C-3 and in part being retained, a process known as the NIH-shift. -!- The 4a-hydroxytetrahydrobiopterin formed can dehydrate to 6,7- dihydrobiopterin, both spontaneously and by the action of EC 4.2.1.96. -!- The 6,7-dihydrobiopterin can be enzymically reduced back to tetrahydrobiopterin, by EC 1.5.1.34, or slowly rearranges into the more stable compound 7,8-dihydrobiopterin. -!- Formerly EC 1.14.3.1 and EC 1.99.1.2.

UniProtKB Entries (1)

P00439
PH4H_HUMAN
Homo sapiens
Phenylalanine-4-hydroxylase

PDB Structure

PDB 1MMT
External Links
Method X-RAY DIFFRACTION
Organism Escherichia
Primary Citation
2.0A resolution crystal structures of the ternary complexes of human phenylalanine hydroxylase catalytic domain with tetrahydrobiopterin and 3-(2-thienyl)-L-alanine or L-norleucine: substrate specificity and molecular motions related to substrate binding
Andersen, O.A., Stokka, A.J., Flatmark, T., Hough, E.
J.Mol.Biol.