1J8U

Catalytic Domain of Human Phenylalanine Hydroxylase Fe(II) in Complex with Tetrahydrobiopterin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.203 
  • R-Value Work: 0.155 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

High resolution crystal structures of the catalytic domain of human phenylalanine hydroxylase in its catalytically active Fe(II) form and binary complex with tetrahydrobiopterin.

Andersen, O.A.Flatmark, T.Hough, E.

(2001) J.Mol.Biol. 314: 279-291

  • DOI: 10.1006/jmbi.2001.5061
  • Primary Citation of Related Structures:  1J8T

  • PubMed Abstract: 
  • The crystal structures of the catalytic domain (DeltaN1-102/DeltaC428-452) of human phenylalanine hydroxylase (hPheOH) in its catalytically competent Fe(II) form and binary complex with the reduced pterin cofactor 6(R)-L-erythro-5,6,7,8-tetrahydrobio ...

    The crystal structures of the catalytic domain (DeltaN1-102/DeltaC428-452) of human phenylalanine hydroxylase (hPheOH) in its catalytically competent Fe(II) form and binary complex with the reduced pterin cofactor 6(R)-L-erythro-5,6,7,8-tetrahydrobiopterin (BH4) have been determined to 1.7 and 1.5 A, respectively. When compared with the structures reported for various catalytically inactive Fe(III) forms, several important differences have been observed, notably at the active site. Thus, the non-liganded hPheOH-Fe(II) structure revealed well defined electron density for only one of the three water molecules reported to be coordinated to the iron in the high-spin Fe(III) form, as well as poor electron density for parts of the coordinating side-chain of Glu330. The reduced cofactor (BH4), which adopts the expected half-semi chair conformation, is bound in the second coordination sphere of the catalytic iron with a C4a-iron distance of 5.9 A. BH4 binds at the same site as L-erythro-7,8-dihydrobiopterin (BH2) in the binary hPheOH-Fe(III)-BH2 complex forming an aromatic pi-stacking interaction with Phe254 and a network of hydrogen bonds. However, compared to that structure the pterin ring is displaced about 0.5 A and rotated about 10 degrees, and the torsion angle between the hydroxyl groups of the cofactor in the dihydroxypropyl side-chain has changed by approximately 120 degrees enabling O2' to make a strong hydrogen bond (2.4 A) with the side-chain oxygen of Ser251. Carbon atoms in the dihydroxypropyl side-chain make several hydrophobic contacts with the protein. The iron is six-coordinated in the binary complex, but the overall coordination geometry is slightly different from that of the Fe(III) form. Most important was the finding that the binding of BH4 causes the Glu330 ligand to change its coordination to the iron when comparing with non-liganded hPheOH-Fe(III) and the binary hPheOH-Fe(III)-BH2 complex.


    Organizational Affiliation

    Department of Chemistry, University of Tromsø, Tromsø, N-9037, Norway.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PHENYLALANINE-4-HYDROXYLASE
A
325Homo sapiensGene Names: PAH
EC: 1.14.16.1
Find proteins for P00439 (Homo sapiens)
Go to Gene View: PAH
Go to UniProtKB:  P00439
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
FE2
Query on FE2

Download SDF File 
Download CCD File 
A
FE (II) ION
Fe
CWYNVVGOOAEACU-UHFFFAOYSA-N
 Ligand Interaction
H4B
Query on H4B

Download SDF File 
Download CCD File 
A
5,6,7,8-TETRAHYDROBIOPTERIN
C9 H15 N5 O3
FNKQXYHWGSIFBK-RPDRRWSUSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.203 
  • R-Value Work: 0.155 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 66.441α = 90.00
b = 108.676β = 90.00
c = 124.418γ = 90.00
Software Package:
Software NamePurpose
SHELXL-97refinement
DENZOdata reduction
CCP4data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-05-22
    Type: Initial release
  • Version 1.1: 2007-10-16
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance