Class of enzymes
Tryptophan hydroxylase (TPH) is an enzyme (EC 1.14.16.4) involved in the synthesis of the monoamine neurotransmitter serotonin. Tyrosine hydroxylase, phenylalanine hydroxylase, and tryptophan hydroxylase together constitute the family of biopterin-dependent aromatic amino acid hydroxylases. TPH catalyzes the following chemical reaction
- L-tryptophan + tetrahydrobiopterin + O2 5-Hydroxytryptophan + dihydrobiopterin + H2O
It employs one additional cofactor, iron.