Full-length human phenylalanine hydroxylase (PAH) in the resting state

  • Classification: OXIDOREDUCTASE
  • Organism(s): Homo sapiens
  • Expression System: Escherichia coli
  • Mutation(s): Yes 

  • Deposited: 2018-11-08 Released: 2019-05-22 
  • Deposition Author(s): Arturo, E.C., Jaffe, E.K.
  • Funding Organization(s): National Institutes of Health/National Institute of Neurological Disorders and Stroke (NIH/NINDS)

Experimental Data Snapshot

  • Resolution: 3.06 Å
  • R-Value Free: 0.238 
  • R-Value Work: 0.203 
  • R-Value Observed: 0.208 

wwPDB Validation   3D Report Full Report

Currently 6N1K does not have a validation slider image.

This is version 1.3 of the entry. See complete history


Biophysical characterization of full-length human phenylalanine hydroxylase provides a deeper understanding of its quaternary structure equilibrium.

Arturo, E.C.Gupta, K.Hansen, M.R.Borne, E.Jaffe, E.K.

(2019) J Biol Chem 294: 10131-10145

  • DOI: https://doi.org/10.1074/jbc.RA119.008294
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Dysfunction of human phenylalanine hydroxylase (hPAH, EC is the primary cause of phenylketonuria, the most common inborn error of amino acid metabolism. The dynamic domain rearrangements of this multimeric protein have thwarted structural study of the full-length form for decades, until now. In this study, a tractable C29S variant of hPAH (C29S) yielded a 3.06 Å resolution crystal structure of the tetrameric resting-state conformation. We used size-exclusion chromatography in line with small-angle X-ray scattering (SEC-SAXS) to analyze the full-length hPAH solution structure both in the presence and absence of Phe, which serves as both substrate and allosteric activators. Allosteric Phe binding favors accumulation of an activated PAH tetramer conformation, which is biophysically distinct in solution. Protein characterization with enzyme kinetics and intrinsic fluorescence revealed that the C29S variant and hPAH are otherwise equivalent in their response to Phe, further supported by their behavior on various chromatography resins and by analytical ultracentrifugation. Modeling of resting-state and activated forms of C29S against SAXS data with available structural data created and evaluated several new models for the transition between the architecturally distinct conformations of PAH and highlighted unique intra- and inter-subunit interactions. Three best-fitting alternative models all placed the allosteric Phe-binding module 8-10 Å farther from the tetramer center than do all previous models. The structural insights into allosteric activation of hPAH reported here may help inform ongoing efforts to treat phenylketonuria with novel therapeutic approaches.

  • Organizational Affiliation

    the Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19102, and.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
A, B, C, D
451Homo sapiensMutation(s): 1 
Gene Names: PAH
UniProt & NIH Common Fund Data Resources
Find proteins for P00439 (Homo sapiens)
Explore P00439 
Go to UniProtKB:  P00439
PHAROS:  P00439
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00439
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

Unit Cell:
Length ( Å )Angle ( ˚ )
a = 72.437α = 90
b = 202.64β = 90.3
c = 72.574γ = 90
Software Package:
Software NamePurpose
XDSdata reduction
XDSdata scaling

Structure Validation

View Full Validation Report

Currently 6N1K does not have a validation slider image.

Entry History & Funding Information

Deposition Data

Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of Neurological Disorders and Stroke (NIH/NINDS)United States1R01NS100081-03

Revision History  (Full details and data files)

  • Version 1.0: 2019-05-22
    Type: Initial release
  • Version 1.1: 2019-07-10
    Changes: Data collection, Database references
  • Version 1.2: 2019-12-18
    Changes: Author supporting evidence
  • Version 1.3: 2023-10-11
    Changes: Data collection, Database references, Derived calculations, Refinement description