4HFI

The GLIC pentameric Ligand-Gated Ion Channel at 2.4 A resolution


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.205 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural basis for ion permeation mechanism in pentameric ligand-gated ion channels.

Sauguet, L.Poitevin, F.Murail, S.Van Renterghem, C.Moraga-Cid, G.Malherbe, L.Thompson, A.W.Koehl, P.Corringer, P.J.Baaden, M.Delarue, M.

(2013) Embo J. 32: 728-741

  • DOI: 10.1038/emboj.2013.17
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • To understand the molecular mechanism of ion permeation in pentameric ligand-gated ion channels (pLGIC), we solved the structure of an open form of GLIC, a prokaryotic pLGIC, at 2.4 Å. Anomalous diffraction data were used to place bound anions and ca ...

    To understand the molecular mechanism of ion permeation in pentameric ligand-gated ion channels (pLGIC), we solved the structure of an open form of GLIC, a prokaryotic pLGIC, at 2.4 Å. Anomalous diffraction data were used to place bound anions and cations. This reveals ordered water molecules at the level of two rings of hydroxylated residues (named Ser6' and Thr2') that contribute to the ion selectivity filter. Two water pentagons are observed, a self-stabilized ice-like water pentagon and a second wider water pentagon, with one sodium ion between them. Single-channel electrophysiology shows that the side-chain hydroxyl of Ser6' is crucial for ion translocation. Simulations and electrostatics calculations complemented the description of hydration in the pore and suggest that the water pentagons observed in the crystal are important for the ion to cross hydrophobic constriction barriers. Simulations that pull a cation through the pore reveal that residue Ser6' actively contributes to ion translocation by reorienting its side chain when the ion is going through the pore. Generalization of these findings to the pLGIC family is proposed.


    Organizational Affiliation

    Unité de Dynamique Structurale des Macromolécules, Institut Pasteur, CNRS UMR3528, Paris, France.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Proton-gated ion channel
A, B, C, D, E
317Gloeobacter violaceus (strain PCC 7421)Gene Names: glvI
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Cys-Loop Receptor Family
Protein: 
Prokaryotic pentameric ligand-gated ion channel (GLIC)
Find proteins for Q7NDN8 (Gloeobacter violaceus (strain PCC 7421))
Go to UniProtKB:  Q7NDN8
Small Molecules
Ligands 5 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NA
Query on NA

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Download CCD File 
A, B, C, D, E
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
ACT
Query on ACT

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Download CCD File 
A, B, C, D, E
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
CL
Query on CL

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Download CCD File 
A, B, C, D, E
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
PLC
Query on PLC

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Download CCD File 
A, B, C, D, E
DIUNDECYL PHOSPHATIDYL CHOLINE
C32 H65 N O8 P
IJFVSSZAOYLHEE-SSEXGKCCSA-O
 Ligand Interaction
LMT
Query on LMT

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Download CCD File 
A, B, C, D, E
DODECYL-BETA-D-MALTOSIDE
C24 H46 O11
NLEBIOOXCVAHBD-QKMCSOCLSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.205 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 181.890α = 90.00
b = 133.200β = 102.74
c = 160.200γ = 90.00
Software Package:
Software NamePurpose
BUSTERrefinement
XDSdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-02-20
    Type: Initial release
  • Version 1.1: 2013-03-20
    Type: Database references