3GUA

Sulfates bound in the vestibule of AChBP


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.10 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.212 
  • R-Value Observed: 0.214 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

An Ion Selectivity Filter in the Extracellular Domain of Cys-loop Receptors Reveals Determinants for Ion Conductance

Hansen, S.B.Wang, H.L.Taylor, P.Sine, S.M.

(2008) J Biol Chem 283: 36066-36070

  • DOI: 10.1074/jbc.C800194200
  • Primary Citation of Related Structures:  
    3GUA

  • PubMed Abstract: 
  • Neurotransmitter binding to Cys-loop receptors promotes a prodigious transmembrane flux of several million ions/s, but to date, structural determinants of ion flux have been identified flanking the membrane-spanning region. Using x-ray crystallography, sequence analysis, and single-channel recording, we identified a novel determinant of ion conductance near the point of entry of permeant ions ...

    Neurotransmitter binding to Cys-loop receptors promotes a prodigious transmembrane flux of several million ions/s, but to date, structural determinants of ion flux have been identified flanking the membrane-spanning region. Using x-ray crystallography, sequence analysis, and single-channel recording, we identified a novel determinant of ion conductance near the point of entry of permeant ions. Co-crystallization of acetylcholine-binding protein with sulfate anions revealed coordination of SO4(2-) with a ring of lysines at a position equivalent to 24 A above the lipid membrane in homologous Cys-loop receptors. Analysis of multiple sequence alignments revealed that residues equivalent to the ring of lysines are negatively charged in cation-selective receptors but are positively charged in anion-selective receptors. Charge reversal of side chains at homologous positions in the nicotinic receptor from the motor end plate decreases unitary conductance up to 80%. Selectivity filters stemming from transmembrane alpha-helices have similar pore diameters and compositions of amino acids. These findings establish that when the channel opens under a physiological electrochemical gradient, permeant ions are initially stabilized within the extracellular vestibule of Cys-loop receptors, and this stabilization is a major determinant of ion conductance.


    Organizational Affiliation

    Department of Pharmacology, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093-0650, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Soluble acetylcholine receptor
A, B, C, D, E, F, G, H, I, J
A, B, C, D, E, F, G, H, I, J
217Aplysia californicaMutation(s): 0 
UniProt
Find proteins for Q8WSF8 (Aplysia californica)
Explore Q8WSF8 
Go to UniProtKB:  Q8WSF8
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ8WSF8
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download Ideal Coordinates CCD File 
AA [auth H],
BA [auth I],
CA [auth I],
DA [auth J],
EA [auth J],
AA [auth H],
BA [auth I],
CA [auth I],
DA [auth J],
EA [auth J],
K [auth A],
L [auth A],
M [auth A],
N [auth A],
O [auth B],
P [auth B],
Q [auth C],
R [auth C],
S [auth D],
T [auth D],
U [auth E],
V [auth E],
W [auth F],
X [auth F],
Y [auth G],
Z [auth H]
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.10 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.212 
  • R-Value Observed: 0.214 
  • Space Group: P 41
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 98.428α = 90
b = 98.428β = 90
c = 265.568γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
AMoREphasing
REFMACrefinement
PDB_EXTRACTdata extraction
HKL-2000data collection

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2009-07-14
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Refinement description, Version format compliance
  • Version 1.2: 2014-09-10
    Changes: Database references
  • Version 1.3: 2017-11-01
    Changes: Refinement description