2WIK

NONAGED FORM OF HUMAN BUTYRYLCHOLINESTERASE INHIBITED BY TABUN ANALOGUE TA6


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.276 
  • R-Value Work: 0.213 
  • R-Value Observed: 0.215 

wwPDB Validation 3D Report Full Report



Literature

Structure-activity analysis of aging and reactivation of human butyrylcholinesterase inhibited by analogues of tabun.

Carletti, E.Aurbek, N.Gillon, E.Loiodice, M.Nicolet, Y.Fontecilla-Camps, J.C.Masson, P.Thiermann, H.Nachon, F.Worek, F.

(2009) Biochem J 421: 97-106

  • DOI: 10.1042/BJ20090091
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • hBChE [human BChE (butyrylcholinesterase)] naturally scavenges OPs (organophosphates). This bioscavenger is currently in Clinical Phase I for pretreatment of OP intoxication. Phosphylated ChEs (cholinesterases) can undergo a spontaneous time-dependen ...

    hBChE [human BChE (butyrylcholinesterase)] naturally scavenges OPs (organophosphates). This bioscavenger is currently in Clinical Phase I for pretreatment of OP intoxication. Phosphylated ChEs (cholinesterases) can undergo a spontaneous time-dependent process called 'aging' during which the conjugate is dealkylated, leading to creation of an enzyme that cannot be reactivated. hBChE inhibited by phosphoramidates such as tabun displays a peculiar resistance to oxime-mediated reactivation. We investigated the basis of oxime resistance of phosphoramidyl-BChE conjugates by determining the kinetics of inhibition, reactivation (obidoxime {1,1'-(oxybis-methylene) bis[4-(hydroxyimino) methyl] pyridinium dichloride}, TMB-4 [1,3-trimethylene-bis(4-hydroxyiminomethylpyridinium) dibromide], HLö 7 {1-[[[4-(aminocarbonyl) pyridinio]methoxy]methyl]-2,4-bis-[(hydroxyimino)methyl] pyridinium dimethanesulfonate)}, HI-6 {1-[[[4-(aminocarbonyl) pyridinio] methoxy] methyl]-2-[(hydroxyimino)methyl]pyridinium dichloride monohydrate} and aging, and the crystal structures of hBChE inhibited by different N-monoalkyl and N,N-dialkyl tabun analogues. The refined structures of aged hBChE conjugates show that aging proceeds through O-dealkylation of the P(R) enantiomer of N,N-diethyl and N-propyl analogues, with subsequent formation of a salt bridge preventing reactivation, similarly to a previous observation made on tabun-ChE conjugates. Interestingly, the N-methyl analogue projects its amino group towards the choline-binding pocket, so that aging proceeds through deamination. This orientation results from a preference of hBChE's acyl-binding pocket for larger than 2-atoms linear substituents. The correlation between the inhibitory potency and the N-monoalkyl chain length is related to increasingly optimized interactions with the acyl-binding pocket as shown by the X-ray structures. These kinetics and X-ray data lead to a structure-activity relationship that highlights steric and electronic effects of the amino substituent of phosphoramidate. This study provides the structural basis to design new oximes capable of reactivating phosphoramidyl-hBChE conjugates after intoxication, notably when hBChE is used as pretreatment, or to design BChE-based catalytic bioscavengers.


    Organizational Affiliation

    Unité d'Enzymologie, Département de Toxicologie, Centre de Recherches du Service de Santé des Armées (CRSSA), 24 av des Maquis du Grésivaudan, 38700 La Tronche, France.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CHOLINESTERASEA529Homo sapiensMutation(s): 3 
Gene Names: BCHECHE1
EC: 3.1.1.8
Find proteins for P06276 (Homo sapiens)
Explore P06276 
Go to UniProtKB:  P06276
NIH Common Fund Data Resources
PHAROS  P06276
Protein Feature View
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  • Reference Sequence
Oligosaccharides
Entity ID: 2
MoleculeChainsChain Length2D Diagram Glycosylation
2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-[beta-L-fucopyranose-(1-6)]2-acetamido-2-deoxy-beta-D-glucopyranose
B, D
3 N-Glycosylation
Entity ID: 3
MoleculeChainsChain Length2D Diagram Glycosylation
beta-L-fucopyranose-(1-6)-2-acetamido-2-deoxy-beta-D-glucopyranose
C
2 N-Glycosylation
Small Molecules
Ligands 5 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAG
Query on NAG

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A
2-acetamido-2-deoxy-beta-D-glucopyranose
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
TC5
Query on TC5

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A
ETHYL HYDROGEN PROPYLAMIDOPHOSPHATE
C5 H14 N O3 P
KZWTXXKNHNYEFB-UHFFFAOYSA-N
 Ligand Interaction
SO4
Query on SO4

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A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
CL
Query on CL

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A
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
NA
Query on NA

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A
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
TC5Kd :  660000   nM  PDBBind
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.276 
  • R-Value Work: 0.213 
  • R-Value Observed: 0.215 
  • Space Group: I 4 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 155.24α = 90
b = 155.24β = 90
c = 127.25γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
XDSdata reduction
XSCALEdata scaling
XDSphasing

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-05-19
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2017-07-12
    Changes: Advisory
  • Version 1.4: 2018-02-28
    Changes: Database references, Source and taxonomy
  • Version 1.5: 2019-01-30
    Changes: Data collection, Experimental preparation
  • Version 1.6: 2019-02-06
    Changes: Data collection, Experimental preparation
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Derived calculations, Other, Structure summary