1KPK

Crystal Structure of the ClC Chloride Channel from E. coli


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.50 Å
  • R-Value Free: 0.301 
  • R-Value Work: 0.290 
  • R-Value Observed: 0.290 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

X-ray structure of a ClC chloride channel at 3.0 A reveals the molecular basis of anion selectivity.

Dutzler, R.Campbell, E.B.Cadene, M.Chait, B.T.MacKinnon, R.

(2002) Nature 415: 287-294

  • DOI: 10.1038/415287a
  • Primary Citation of Related Structures:  
    1KPK, 1KPL

  • PubMed Abstract: 
  • The ClC chloride channels catalyse the selective flow of Cl- ions across cell membranes, thereby regulating electrical excitation in skeletal muscle and the flow of salt and water across epithelial barriers. Genetic defects in ClC Cl- channels underlie several familial muscle and kidney diseases ...

    The ClC chloride channels catalyse the selective flow of Cl- ions across cell membranes, thereby regulating electrical excitation in skeletal muscle and the flow of salt and water across epithelial barriers. Genetic defects in ClC Cl- channels underlie several familial muscle and kidney diseases. Here we present the X-ray structures of two prokaryotic ClC Cl- channels from Salmonella enterica serovar typhimurium and Escherichia coli at 3.0 and 3.5 A, respectively. Both structures reveal two identical pores, each pore being formed by a separate subunit contained within a homodimeric membrane protein. Individual subunits are composed of two roughly repeated halves that span the membrane with opposite orientations. This antiparallel architecture defines a selectivity filter in which a Cl- ion is stabilized by electrostatic interactions with alpha-helix dipoles and by chemical coordination with nitrogen atoms and hydroxyl groups. These findings provide a structural basis for further understanding the function of ClC Cl- channels, and establish the physical and chemical basis of their anion selectivity.


    Organizational Affiliation

    Howard Hughes Medical Institute, Laboratory of Molecular Neurobiology and Biophysics, Rockefeller University, 1230 York Avenue, New York, New York 10021, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
putative channel transporter
A, B, C, D, E, F
A, B, C, D, E, F
473Escherichia coliMutation(s): 0 
Gene Names: yadQ
Membrane Entity: Yes 
UniProt
Find proteins for P37019 (Escherichia coli (strain K12))
Explore P37019 
Go to UniProtKB:  P37019
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP37019
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.50 Å
  • R-Value Free: 0.301 
  • R-Value Work: 0.290 
  • R-Value Observed: 0.290 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 105.66α = 90
b = 152.525β = 90
c = 263.064γ = 90
Software Package:
Software NamePurpose
AMoREphasing
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2002-01-23
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance