3EJ5

complex of Ricin A chain and pyrimidine-based inhibitor


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.194 
  • R-Value Observed: 0.198 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

The X-ray structure of ricin A chain with a novel inhibitor

Bai, Y.Monzingo, A.F.Robertus, J.D.

(2009) Arch Biochem Biophys 483: 23-28

  • DOI: 10.1016/j.abb.2008.12.013
  • Primary Citation of Related Structures:  
    3EJ5

  • PubMed Abstract: 
  • Ricin is a potent heterodimeric cytotoxin; the B chain binds eucaryotic cell surfaces aiding uptake and the A chain, RTA, reaches the cytoplasm where it enzymatically depurinates a key ribosomal adenine, inhibiting protein synthesis. Ricin is known to be ...

    Ricin is a potent heterodimeric cytotoxin; the B chain binds eucaryotic cell surfaces aiding uptake and the A chain, RTA, reaches the cytoplasm where it enzymatically depurinates a key ribosomal adenine, inhibiting protein synthesis. Ricin is known to be an agent in bioterrorist repertoires and there is great interest in finding, or creating, efficacious inhibitors of the toxin as potential antidotes. We have previously identified two families of bicyclic RTA inhibitors, pterins and purines. Both classes have poor solubility which impairs inhibitor development. Here we report the use of 2-amino-4,6-dihydroxy-pyrimidines as RTA inhibitors. Unlike previously observed single ring inhibitor platforms, these displace Tyr 80 and bind deep in the RTA specificity pocket. These compounds are at least 10 times more soluble than pterin-based inhibitors and appear to be useful new class of ricin inhibitors.


    Organizational Affiliation

    Institute for Cellular and Molecular Biology, Department of Chemistry and Biochemistry, University of Texas, Austin, 78712, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Ricin A chain X257Ricinus communisMutation(s): 0 
EC: 3.2.2.22
Find proteins for P02879 (Ricinus communis)
Explore P02879 
Go to UniProtKB:  P02879
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EJ5
Query on EJ5

Download Ideal Coordinates CCD File 
X
4-[3-(2-amino-4-hydroxy-6-oxo-1,6-dihydropyrimidin-5-yl)propyl]benzoic acid
C14 H15 N3 O4
GBBVOAWLGQEGEW-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
EJ5IC50:  270000   nM  Binding MOAD
EJ5IC50 :  270000   nM  PDBBind
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.194 
  • R-Value Observed: 0.198 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 42.642α = 90
b = 68.006β = 112.97
c = 49.675γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
REFMACrefinement
PDB_EXTRACTdata extraction
MAR345dtbdata collection
HKL-2000data reduction
MOLREPphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-04-07
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Version format compliance
  • Version 1.2: 2017-10-25
    Changes: Refinement description