3PJS

Mechanism of Activation Gating in the Full-Length KcsA K+ Channel


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.80 Å
  • R-Value Free: 0.332 
  • R-Value Work: 0.281 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Mechanism of activation gating in the full-length KcsA K+ channel.

Uysal, S.Cuello, L.G.Cortes, D.M.Koide, S.Kossiakoff, A.A.Perozo, E.

(2011) Proc Natl Acad Sci U S A 108: 11896-11899

  • DOI: 10.1073/pnas.1105112108
  • Primary Citation of Related Structures:  
    3PJS

  • PubMed Abstract: 
  • Using a constitutively active channel mutant, we solved the structure of full-length KcsA in the open conformation at 3.9 Å. The structure reveals that the activation gate expands about 20 Å, exerting a strain on the bulge helices in the C-terminal d ...

    Using a constitutively active channel mutant, we solved the structure of full-length KcsA in the open conformation at 3.9 Å. The structure reveals that the activation gate expands about 20 Å, exerting a strain on the bulge helices in the C-terminal domain and generating side windows large enough to accommodate hydrated K(+) ions. Functional and spectroscopic analysis of the gating transition provides direct insight into the allosteric coupling between the activation gate and the selectivity filter. We show that the movement of the inner gate helix is transmitted to the C-terminus as a straightforward expansion, leading to an upward movement and the insertion of the top third of the bulge helix into the membrane. We suggest that by limiting the extent to which the inner gate can open, the cytoplasmic domain also modulates the level of inactivation occurring at the selectivity filter.


    Organizational Affiliation

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



Macromolecules
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Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
FAB light chainAC215Mus musculusMutation(s): 0 
Protein Feature View
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  • Reference Sequence
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Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
FAB heavy chainBD224Mus musculusMutation(s): 0 
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  • Reference Sequence
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Entity ID: 3
MoleculeChainsSequence LengthOrganismDetailsImage
Voltage-gated potassium channelKLMN166Streptomyces lividansMutation(s): 7 
Gene Names: kcsAskc1
Find proteins for P0A334 (Streptomyces lividans)
Explore P0A334 
Go to UniProtKB:  P0A334
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.80 Å
  • R-Value Free: 0.332 
  • R-Value Work: 0.281 
  • Space Group: I 2 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 118.266α = 90
b = 176.716β = 90
c = 340.466γ = 90
Software Package:
Software NamePurpose
MAR345dtbdata collection
PHASERphasing
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-07-06
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2011-07-20
    Changes: Database references
  • Version 1.3: 2011-08-03
    Changes: Database references