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Allosteric regulation of phenylalanine hydroxylase.

ABSTRACT: The liver enzyme phenylalanine hydroxylase is responsible for conversion of excess phenylalanine in the diet to tyrosine. Phenylalanine hydroxylase is activated by phenylalanine; this activation is inhibited by the physiological reducing substrate tetrahydrobiopterin. Phosphorylation of Ser16 lowers the concentration of phenylalanine for activation. This review discusses the present understanding of the molecular details of the allosteric regulation of the enzyme.

SUBMITTER: Fitzpatrick PF

PROVIDER: S-EPMC3271142 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Allosteric regulation of phenylalanine hydroxylase.

Fitzpatrick Paul F PF

Archives of biochemistry and biophysics 20111007 2

The liver enzyme phenylalanine hydroxylase is responsible for conversion of excess phenylalanine in the diet to tyrosine. Phenylalanine hydroxylase is activated by phenylalanine; this activation is inhibited by the physiological reducing substrate tetrahydrobiopterin. Phosphorylation of Ser16 lowers the concentration of phenylalanine for activation. This review discusses the present understanding of the molecular details of the allosteric regulation of the enzyme. ...[more]

PMID: 22005392

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