Phenylalanine binding is linked to dimerization of the regulatory domain of phenylalanine hydroxylase.
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ABSTRACT:
SUBMITTER: Zhang S
PROVIDER: S-EPMC4251497 | biostudies-literature | 2014 Oct
REPOSITORIES: biostudies-literature
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Phenylalanine binding is linked to dimerization of the regulatory domain of phenylalanine hydroxylase.
Zhang Shengnan S Roberts Kenneth M KM Fitzpatrick Paul F PF
Biochemistry 20141013 42
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 i ...[more]
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