4MX1

Structure of ricin A chain bound with 2-amino-4-oxo-N-(2-(3-phenylureido)ethyl)-3,4-dihydropteridine-7-carboxamide

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.59 Å
  • R-Value Free: 0.261 
  • R-Value Work: 0.227 
  • R-Value Observed: 0.229 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history. 


Literature

Sulfur incorporation generally improves Ricin inhibition in pterin-appended glycine-phenylalanine dipeptide mimics.

Wiget, P.A., Manzano, L.A., Pruet, J.M., Gao, G., Saito, R., Monzingo, A.F., Jasheway, K.R., Robertus, J.D., Anslyn, E.V.

(2013) Bioorg Med Chem Lett 23: 6799-6804

  • DOI: 10.1016/j.bmcl.2013.10.017
  • Primary Citation of Related Structures:  
    4MX1, 4MX5

  • PubMed Abstract: 

    • Several 7-aminoamido-pterins were synthesized to evaluate the electronic and biochemical subtleties observed in the 'linker space' when N-{N-(pterin-7-yl)carbonylglycyl}-l-phenylalanine 1 was bound to the active site of RTA. The gylcine-phenylalanine dipeptide analogs included both amides and thioamides ...

    Several 7-aminoamido-pterins were synthesized to evaluate the electronic and biochemical subtleties observed in the 'linker space' when N-{N-(pterin-7-yl)carbonylglycyl}-l-phenylalanine 1 was bound to the active site of RTA. The gylcine-phenylalanine dipeptide analogs included both amides and thioamides. Decarboxy gly-phe analog 2 showed a 6.4-fold decrease in potency (IC50 = 128 μM), yet the analogous thioamide 7 recovered the lost activity and performed similarly to the parent inhibitor (IC50 = 29 μM). Thiourea 12 exhibited an IC50 nearly six times lower than the oxo analog 13. All inhibitors showed the pterin head-group firmly bound in their X-ray structures yet the pendants were not fully resolved suggesting that all pendants are not firmly bound in the RTA linker space. Calculated log P values do not correlate to the increase in bioactivity suggesting other factors dominate.

    Organizational Affiliation: 

    Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA.



Macromolecules
Find similar proteins by: 
(by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Ricin A chain A268Ricinus 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 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
1MX
Query on 1MX
Download Ideal Coordinates CCD File 
A
2-amino-4-oxo-N-{2-[(phenylcarbamoyl)amino]ethyl}-3,4-dihydropteridine-7-carboxamide
C16 H16 N8 O3
UGNDSTADFKFZJF-UHFFFAOYSA-N		 Ligand Interaction
MLA
Query on MLA
Download Ideal Coordinates CCD File 
A
MALONIC ACID
C3 H4 O4
OFOBLEOULBTSOW-UHFFFAOYSA-N		 Ligand Interaction
SO4
Query on SO4
Download Ideal Coordinates CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L		 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
1MXIC50:  209000   nM  BindingDB
1MXIC50:  209000   nM  Binding MOAD
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.59 Å
  • R-Value Free: 0.261 
  • R-Value Work: 0.227 
  • R-Value Observed: 0.229 
  • Space Group: P 41 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 68.102α = 90
b = 68.102β = 90
c = 140.532γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
REFMACrefinement
PDB_EXTRACTdata extraction
BOSdata collection
HKL-2000data reduction
HKL-2000data scaling
MOLREPphasing

Structure Validation

View Full Validation Report


View more in-depth experimental data

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-01-15
    Type: Initial release
  • Version 1.1: 2014-02-12
    Changes: Database references
  • Version 1.2: 2015-04-29
    Changes: Non-polymer description
  • Version 1.3: 2017-11-15
    Changes: Refinement description