4PAH

HUMAN PHENYLALANINE HYDROXYLASE CATALYTIC DOMAIN DIMER WITH BOUND NOR-ADRENALINE INHIBITOR


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.208 
  • R-Value Work: 0.169 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Crystallographic analysis of the human phenylalanine hydroxylase catalytic domain with bound catechol inhibitors at 2.0 A resolution.

Erlandsen, H.Flatmark, T.Stevens, R.C.Hough, E.

(1998) Biochemistry 37: 15638-15646

  • DOI: 10.1021/bi9815290
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The aromatic amino acid hydroxylases represent a superfamily of structurally and functionally closely related enzymes, one of those functions being reversible inhibition by catechol derivatives. Here we present the crystal structure of the dimeric ca ...

    The aromatic amino acid hydroxylases represent a superfamily of structurally and functionally closely related enzymes, one of those functions being reversible inhibition by catechol derivatives. Here we present the crystal structure of the dimeric catalytic domain (residues 117-424) of human phenylalanine hydroxylase (hPheOH), cocrystallized with various potent and well-known catechol inhibitors and refined at a resolution of 2.0 A. The catechols bind by bidentate coordination to each iron in both subunits of the dimer through the catechol hydroxyl groups, forming a blue-green colored ligand-to-metal charge-transfer complex. In addition, Glu330 and Tyr325 are identified as determinant residues in the recognition of the inhibitors. In particular, the interaction with Glu330 conforms to the structural explanation for the pH dependence of catecholamine binding to PheOH, with a pKa value of 5.1 (20 degreesC). The overall structure of the catechol-bound enzyme is very similar to that of the uncomplexed enzyme (rms difference of 0.2 A for the Calpha atoms). Most striking is the replacement of two iron-bound water molecules with catechol hydroxyl groups. This change is consistent with a change in the ligand field symmetry of the high-spin (S = 5/2) Fe(III) from a rhombic to a nearly axial ligand field symmetry as seen upon noradrenaline binding using EPR spectroscopy [Martinez, A., Andersson, K. K., Haavik, J., and Flatmark, T. (1991) Eur. J. Biochem. 198, 675-682]. Crystallographic comparison with the structurally related rat tyrosine hydroxylase binary complex with the oxidized cofactor 7,8-dihydrobiopterin revealed overlapping binding sites for the catechols and the cofactor, compatible with a competitive type of inhibition of the catechols versus BH4. The comparison demonstrates some structural differences at the active site as the potential basis for the different substrate specificity of the two enzymes.


    Organizational Affiliation

    Protein Crystallography Group, Chemistry Department, University of Tromso, Norway.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PHENYLALANINE HYDROXYLASE
A
308Homo sapiensMutation(s): 0 
Gene 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
LNR
Query on LNR

Download SDF File 
Download CCD File 
A
L-NOREPINEPHRINE
NORADRENALINE
C8 H11 N O3
SFLSHLFXELFNJZ-QMMMGPOBSA-N
 Ligand Interaction
FE
Query on FE

Download SDF File 
Download CCD File 
A
FE (III) ION
Fe
VTLYFUHAOXGGBS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.208 
  • R-Value Work: 0.169 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 66.780α = 90.00
b = 108.730β = 90.00
c = 125.460γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
CNSphasing
SCALEPACKdata scaling
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-04-27
    Type: Initial release
  • Version 1.1: 2008-03-25
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2013-02-20
    Type: Atomic model