EC 1.14 - Acting on paired donors, with incorporation or reduction of molecular oxygen. The oxygen incorporated need not be derived from O2
EC 220.127.116.11 - Phenylalanine 4-monooxygenase
IntEnz Enzyme Nomenclature
20276 [IUBMB](6R)-L-erythro-5,6,7,8-tetrahydrobiopterin(6R)-L-erythro-5,6,7,8-tetrahydrobiopterinName origin: UniProt - CHECKED (C)Formula: C9H15N5O3
Charge: 0ChEBI compound status: CHECKED (C)L-phenylalanineL-phenylalanineName origin: UniProt - CHECKED (C)Formula: C9H11NO2
Charge: 0ChEBI compound status: CHECKED (C)O2O2Name origin: UniProt - CHECKED (C)Formula: O2
Charge: 0ChEBI compound status: CHECKED (C)<=>4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterin4a-hydroxy-L-erythro-5,6,7,8-tetrahydrobiopterinName origin: UniProt - CHECKED (C)Formula: C9H15N5O4
Charge: 0ChEBI compound status: CHECKED (C)
The active centre contains mononuclear iron(II). The reaction involves an arene oxide that rearranges to give the phenolic hydroxy group. This results in the hydrogen at C-4 migrating to C-3 and in part being retained. This process is known as the NIH-shift. The 4a-hydroxytetrahydrobiopterin formed can dehydrate to 6,7-dihydrobiopterin, both spontaneously and by the action of EC 18.104.22.168, 4a-hydroxytetrahydrobiopterin dehydratase. The 6,7-dihydrobiopterin can be enzymically reduced back to tetrahydrobiopterin, by EC 22.214.171.124, 6,7-dihydropteridine reductase, or slowly rearranges into the more stable compound 7,8-dihydrobiopterin.
Links to other databases
Phenylalanine hydroxylation by Pseudomonas species (ATCC 11299a). Nature of the cofactor.J. Biol. Chem. 244: 142-146 (1969). [PMID: 5773277]
Studies on the mechanism of the enzymic conversion of phenylalanine to tyrosine.J. Biol. Chem. 234: 2677-2682 (1959).
Studies on partially purified phenylalanine hydroxylase.Arch. Biochem. Biophys. 60: 476-484 (1956).
The enzymic conversion of phenylalanine to tyrosine.J. Biol. Chem. 194: 503-511 (1952).
Mechanism of metal-independent hydroxylation by Chromobacterium violaceum phenylalanine hydroxylase.Biochemistry 34: 7525-7532 (1995). [PMID: 7779797]
High resolution crystal structures of the catalytic domain of human phenylalanine hydroxylase in its catalytically active Fe(II) form and binary complex with tetrahydrobiopterin.J. Mol. Biol. 314: 266-278 (2001). [PMID: 11718561]
Structural comparison of bacterial and human iron-dependent phenylalanine hydroxylases: similar fold, different stability and reaction rates.J. Mol. Biol. 320: 645-661 (2002). [PMID: 12096915]
[EC 126.96.36.199 created 1961 as EC 188.8.131.52, transferred 1965 to EC 184.108.40.206, transferred 1972 to EC 220.127.116.11, modified 2002, modified 2003]