1DBR

HYPOXANTHINE GUANINE XANTHINE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Work: 0.168 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Crystal structures of Toxoplasma gondii HGXPRTase reveal the catalytic role of a long flexible loop.

Schumacher, M.A.Carter, D.Ross, D.S.Ullman, B.Brennan, R.G.

(1996) Nat Struct Biol 3: 881-887

  • DOI: https://doi.org/10.1038/nsb1096-881
  • Primary Citation of Related Structures:  
    1DBR

  • PubMed Abstract: 

    Crystal structures of substrate-free and XMP-soaked hypoxanthine-guanine-xanthine phosphoribosyltransferase (HGXPRTase) of the opportunistic pathogen Toxoplasma gondii have been determined to 2.4 and 2.9 A resolution, respectively. HGXPRTase displays the conserved PRTase fold. In the structure of the enzyme bound to its product, a long flexible loop (residues 115-126) is located away from the active site. Comparison to the substrate-free structure reveals a striking relocation of the loop, which is poised to cover the catalytic pocket, thus providing a mechanism by which the HG(X)PRTases shield their oxocarbonium transition states from nucleophilic attack by the bulk solvent. The conserved Ser 117-Tyr 118 dipeptide within the loop is brought to the active site, completing the ensemble of catalytic residues.


  • Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Oregon Health Sciences University, Portland 97201-3098, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
HYPOXANTHINE GUANINE XANTHINE PHOSPHORIBOSYLTRANSFERASE
A, B, C, D
231Toxoplasma gondiiMutation(s): 0 
UniProt
Find proteins for Q26997 (Toxoplasma gondii)
Explore Q26997 
Go to UniProtKB:  Q26997
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ26997
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Work: 0.168 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 65.15α = 90
b = 109.22β = 111.8
c = 79.74γ = 90
Software Package:
Software NamePurpose
TNTrefinement

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1997-12-03
    Type: Initial release
  • Version 1.1: 2008-03-03
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2024-02-07
    Changes: Data collection, Database references, Derived calculations, Other