3STL

KcsA potassium channel mutant Y82C with Cadmium bound


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Free: 0.263 
  • R-Value Work: 0.227 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Mechanism of Cd(2+) Coordination during Slow Inactivation in Potassium Channels.

Raghuraman, H.Cordero-Morales, J.F.Jogini, V.Pan, A.C.Kollewe, A.Roux, B.Perozo, E.

(2012) Structure 20: 1332-1342

  • DOI: 10.1016/j.str.2012.03.027
  • Primary Citation of Related Structures:  
    3STL, 3STZ

  • PubMed Abstract: 
  • In K+ channels, rearrangements of the pore outer vestibule have been associated with C-type inactivation gating. Paradoxically, the crystal structure of Open/C-type inactivated KcsA suggests these movements to be modest in magnitude. In this study, w ...

    In K+ channels, rearrangements of the pore outer vestibule have been associated with C-type inactivation gating. Paradoxically, the crystal structure of Open/C-type inactivated KcsA suggests these movements to be modest in magnitude. In this study, we show that under physiological conditions, the KcsA outer vestibule undergoes relatively large dynamic rearrangements upon inactivation. External Cd2+ enhances the rate of C-type inactivation in an cysteine mutant (Y82C) via metal-bridge formation. This effect is not present in a non-inactivating mutant (E71A/Y82C). Tandem dimer and tandem tetramer constructs of equivalent cysteine mutants in KcsA and Shaker K+ channels demonstrate that these Cd2+ metal bridges are formed only between adjacent subunits. This is well supported by molecular dynamics simulations. Based on the crystal structure of Cd2+ -bound Y82C-KcsA in the closed state, together with electron paramagnetic resonance distance measurements in the KcsA outer vestibule, we suggest that subunits must dynamically come in close proximity as the channels undergo inactivation.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA.



Macromolecules
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Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
antibody Fab fragment heavy chainA219Mus musculusMutation(s): 0 
Protein Feature View
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  • Reference Sequence
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Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
antibody Fab fragment light chainB212Mus musculusMutation(s): 0 
Protein Feature View
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  • Reference Sequence
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Entity ID: 3
MoleculeChainsSequence LengthOrganismDetailsImage
Voltage-gated potassium channelC103Streptomyces lividansMutation(s): 1 
Gene Names: kcsAskc1
Membrane protein
Mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Channels: Potassium, Sodium, & Proton Ion-Selective
Protein: 
KcsA Y82C with bound Cadmium
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: 2.40 Å
  • R-Value Free: 0.263 
  • R-Value Work: 0.227 
  • Space Group: I 4
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 155.907α = 90
b = 155.907β = 90
c = 76.119γ = 90
Software Package:
Software NamePurpose
ADSCdata collection
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling
CNSphasing

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-04-18
    Type: Initial release
  • Version 1.1: 2012-10-03
    Changes: Database references