2DFP

X-RAY STRUCTURE OF AGED DI-ISOPROPYL-PHOSPHORO-FLUORIDATE (DFP) BOUND TO ACETYLCHOLINESTERASE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.30 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.186 

wwPDB Validation   3D Report Full Report


This is version 2.1 of the entry. See complete history


Literature

Crystal structures of aged phosphonylated acetylcholinesterase: nerve agent reaction products at the atomic level.

Millard, C.B.Kryger, G.Ordentlich, A.Greenblatt, H.M.Harel, M.Raves, M.L.Segall, Y.Barak, D.Shafferman, A.Silman, I.Sussman, J.L.

(1999) Biochemistry 38: 7032-7039

  • DOI: 10.1021/bi982678l
  • Primary Citation of Related Structures:  
    1SOM, 2DFP, 1CFJ

  • PubMed Abstract: 
  • Organophosphorus acid anhydride (OP) nerve agents are potent inhibitors which rapidly phosphonylate acetylcholinesterase (AChE) and then may undergo an internal dealkylation reaction (called "aging") to produce an OP-enzyme conjugate that cannot be reactivated ...

    Organophosphorus acid anhydride (OP) nerve agents are potent inhibitors which rapidly phosphonylate acetylcholinesterase (AChE) and then may undergo an internal dealkylation reaction (called "aging") to produce an OP-enzyme conjugate that cannot be reactivated. To understand the basis for irreversible inhibition, we solved the structures of aged conjugates obtained by reaction of Torpedo californica AChE (TcAChE) with diisopropylphosphorofluoridate (DFP), O-isopropylmethylphosponofluoridate (sarin), or O-pinacolylmethylphosphonofluoridate (soman) by X-ray crystallography to 2.3, 2.6, or 2.2 A resolution, respectively. The highest positive difference density peak corresponded to the OP phosphorus and was located within covalent bonding distance of the active-site serine (S200) in each structure. The OP-oxygen atoms were within hydrogen-bonding distance of four potential donors from catalytic subsites of the enzyme, suggesting that electrostatic forces significantly stabilize the aged enzyme. The active sites of aged sarin- and soman-TcAChE were essentially identical and provided structural models for the negatively charged, tetrahedral intermediate that occurs during deacylation with the natural substrate, acetylcholine. Phosphorylation with DFP caused an unexpected movement in the main chain of a loop that includes residues F288 and F290 of the TcAChE acyl pocket. This is the first major conformational change reported in the active site of any AChE-ligand complex, and it offers a structural explanation for the substrate selectivity of AChE.


    Related Citations: 
    • Atomic Structure of Acetylcholinesterase from Torpedo Californica: A Prototypic Acetylcholine-Binding Protein
      Sussman, J.L., Harel, M., Frolow, F., Oefner, C., Goldman, A., Toker, L., Silman, I.
      (1991) Science 253: 872

    Organizational Affiliation

    Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel. 1imill@sgjs6.weizmann.ac.il



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
PROTEIN (ACETYLCHOLINESTERASE)A534Tetronarce californicaMutation(s): 0 
Gene Names: ache
EC: 3.1.1.7
UniProt
Find proteins for P04058 (Tetronarce californica)
Explore P04058 
Go to UniProtKB:  P04058
Protein Feature View
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  • Reference Sequence
Oligosaccharides

Help

Entity ID: 2
MoleculeChainsChain Length2D DiagramGlycosylation3D Interactions
2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranoseB, C2N-Glycosylation Oligosaccharides Interaction
Glycosylation Resources
GlyTouCan:  G42666HT
GlyCosmos:  G42666HT
GlyGen:  G42666HT
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAG
Query on NAG

Download Ideal Coordinates CCD File 
D [auth A]2-acetamido-2-deoxy-beta-D-glucopyranose
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
MES
Query on MES

Download Ideal Coordinates CCD File 
E [auth A]2-(N-MORPHOLINO)-ETHANESULFONIC ACID
C6 H13 N O4 S
SXGZJKUKBWWHRA-UHFFFAOYSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MIS
Query on MIS
AL-PEPTIDE LINKINGC6 H14 N O6 PSER
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.30 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.186 
  • Space Group: P 31 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 112.636α = 90
b = 112.636β = 90
c = 136.881γ = 120
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
CNSrefinement
CNSphasing

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1999-06-28
    Type: Initial release
  • Version 1.1: 2007-10-16
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Non-polymer description, Version format compliance
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Derived calculations, Structure summary
  • Version 2.1: 2021-06-02
    Changes: Derived calculations, Structure summary