3EFD

The crystal structure of the cytoplasmic domain of KcsA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.276 
  • R-Value Work: 0.225 
  • R-Value Observed: 0.230 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Crystal structure of full-length KcsA in its closed conformation.

Uysal, S.Vasquez, V.Tereshko, V.Esaki, K.Fellouse, F.A.Sidhu, S.S.Koide, S.Perozo, E.Kossiakoff, A.

(2009) Proc Natl Acad Sci U S A 106: 6644-6649

  • DOI: 10.1073/pnas.0810663106
  • Primary Citation of Related Structures:  
    3EFD, 3EFF

  • PubMed Abstract: 
  • KcsA is a proton-activated, voltage-modulated K(+) channel that has served as the archetype pore domain in the Kv channel superfamily. Here, we have used synthetic antigen-binding fragments (Fabs) as crystallographic chaperones to determine the struc ...

    KcsA is a proton-activated, voltage-modulated K(+) channel that has served as the archetype pore domain in the Kv channel superfamily. Here, we have used synthetic antigen-binding fragments (Fabs) as crystallographic chaperones to determine the structure of full-length KcsA at 3.8 A, as well as that of its isolated C-terminal domain at 2.6 A. The structure of the full-length KcsA-Fab complex reveals a well-defined, 4-helix bundle that projects approximately 70 A toward the cytoplasm. This bundle promotes a approximately 15 degree bending in the inner bundle gate, tightening its diameter and shifting the narrowest point 2 turns of helix below. Functional analysis of the full-length KcsA-Fab complex suggests that the C-terminal bundle remains whole during gating. We suggest that this structure likely represents the physiologically relevant closed conformation of KcsA.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, and Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637, USA.



Macromolecules
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Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
FabLL211Mus musculusMutation(s): 0 
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
FabHH222Mus musculusMutation(s): 0 
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetailsImage
KcsAK30Escherichia coliMutation(s): 0 
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.276 
  • R-Value Work: 0.225 
  • R-Value Observed: 0.230 
  • Space Group: I 4
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 115.499α = 90
b = 115.499β = 90
c = 76.816γ = 90
Software Package:
Software NamePurpose
ADSCdata collection
CCP4model building
REFMACrefinement
HKL-2000data reduction
HKL-2000data scaling
CCP4phasing

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-04-14
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Refinement description, Version format compliance