Phenylalanine binding is linked to dimerization of the regulatory domain of phenylalanine hydroxylase.

ABSTRACT: Analytical ultracentrifugation has been used to analyze the oligomeric structure of the isolated regulatory domain of phenylalanine hydroxylase. The protein exhibits a monomer-dimer equilibrium with a dissociation constant of ~46 μM; this value is unaffected by the removal of the 24 N-terminal residues or by phosphorylation of Ser16. In contrast, phenylalanine binding (Kd = 8 μM) stabilizes the dimer. These results suggest that dimerization of the regulatory domain of phenylalanine hydroxylase is linked to allosteric activation of the enzyme.

SUBMITTER: Zhang S 

PROVIDER: S-EPMC4251497 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature