TY - CHAP M1 - Book, Section TI - Structural Studies of Phenylalanine Hydroxylase Enzyme A1 - Erlandsen, Heidi A1 - Stevens, Raymond C. A2 - Valle, David L. A2 - Antonarakis, Stylianos A2 - Ballabio, Andrea A2 - Beaudet, Arthur L. A2 - Mitchell, Grant A. Y1 - 2019 N1 - 10.1036/Ommbid.99 T2 - The Online Metabolic and Molecular Bases of Inherited Disease AB - Recombinant human (liver) phenylalanine hydroxylase (PheOH, phenylalanine 4-monooxygenase, EC 1.14.16.1) is reported to exist in solution as a pH-dependent equilibrium between homotetramers and homodimers (Martinez et al,34). The molecular weight of one subunit is approximately 50 kDa (between 50 and 53 kDa). It has an absolute requirement for ferrous iron to be active, and uses the cofactors BH4 and O2 to perform the hydroxylation reaction. PheOH, like the two other aromatic amino acid hydroxylases tyrosine hydroxylase (TyrOH, tyrosine 3-monooxygenase, EC 1.14.16.2) and tryptophan hydroxylase (TrpOH, tryptophan 5-monooxygenase, EC 1.14.16.4), consists of three domains: the regulatory domain (residues 1-142), the catalytic domain (residues 143-410), and a short tetramerization domain (residues 411-452). SN - PB - McGraw-Hill Education CY - New York, NY M3 - doi: 10.1036/Ommbid.99 Y2 - 2024/10/10 UR - ommbid.mhmedical.com/content.aspx?aid=1181421745 ER -