2V6S

Medium resolution crystal structure of pterin-4a-carbinolamine dehydratase from Toxoplasma gondii


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.22 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.178 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal Structures of Toxoplasma Gondii Pterin-4A-Carbinolamine Dehydratase and Comparisons with Mammalian and Parasite Orthologues.

Cameron, S.Fyffe, S.A.Goldie, S.Hunter, W.N.

(2008) Mol.Biochem.Parasitol. 158: 131

  • DOI: 10.1016/j.molbiopara.2007.12.002
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The enzyme pterin-4a-carbinolamine dehydratase (PCD) is important for the recycling of pterins within eukaryotic cells. A recombinant expression system for PCD from the apicomplexan parasite Toxoplasma gondii has been prepared, the protein purified a ...

    The enzyme pterin-4a-carbinolamine dehydratase (PCD) is important for the recycling of pterins within eukaryotic cells. A recombinant expression system for PCD from the apicomplexan parasite Toxoplasma gondii has been prepared, the protein purified and crystallised. Single crystal X-ray diffraction methods have produced a high-resolution structure (1.6A) of the apo-enzyme and a low-resolution structure (3.1A) of a complex with a substrate-like ligand dihydrobiopterin (BH(2)). Analysis of the hydrogen bonding interactions that contribute to binding BH(2) suggest that the ligand is present in an enol tautomeric state, which makes it more similar to the physiological substrate. The enzyme can process (R)- and (S)-forms of pterin-4a-carbinolamine and the ligand complex suggests that His61 and His79 are placed to act independently as general bases for catalysis of the individual enantiomers. Comparisons with orthologues from other protozoan parasites (Plasmodium falciparum and Leishmania major) and with rat PCD, for which the structure is known, indicate a high degree of sequence and structure conservation of this enzyme. The molecular determinants of ligand recognition and PCD reactivity are therefore highly conserved across species.


    Organizational Affiliation

    Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PTERIN-4A-CARBINOLAMINE DEHYDRATASE
A, B
106Toxoplasma gondiiMutation(s): 0 
Gene Names: pcd
EC: 4.2.1.96
Find proteins for Q2Q449 (Toxoplasma gondii)
Go to UniProtKB:  Q2Q449
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.22 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.178 
  • Space Group: P 43 21 2
Unit Cell:
Length (Å)Angle (°)
a = 119.750α = 90.00
b = 119.750β = 90.00
c = 49.330γ = 90.00
Software Package:
Software NamePurpose
SCALAdata scaling
MOSFLMdata reduction
REFMACrefinement
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-07-22
    Type: Initial release
  • Version 1.1: 2011-06-02
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance