2OGU

Crystal structure of the isolated MthK RCK domain


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.23 Å
  • R-Value Free: 0.299 
  • R-Value Work: 0.232 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Dynamic oligomeric conversions of the cytoplasmic RCK domains mediate MthK potassium channel activity.

Kuo, M.M.Baker, K.A.Wong, L.Choe, S.

(2007) Proc.Natl.Acad.Sci.Usa 104: 2151-2156

  • DOI: 10.1073/pnas.0609085104

  • PubMed Abstract: 
  • The crystal structure of the RCK-containing MthK provides a molecular framework for understanding the ligand gating mechanisms of K+ channels. Here we examined the macroscopic currents of MthK in enlarged Escherichia coli membrane by patch clamp and ...

    The crystal structure of the RCK-containing MthK provides a molecular framework for understanding the ligand gating mechanisms of K+ channels. Here we examined the macroscopic currents of MthK in enlarged Escherichia coli membrane by patch clamp and rapid perfusion techniques and showed that the channel undergoes desensitization in seconds after activation by Ca2+ or Cd2+. Additionally, MthK is inactivated by slightly acidic pH only from the cytoplasmic side. Examinations of isolated RCK domain by size-exclusion chromatography, static light scattering, analytical sedimentation, and stopped-flow spectroscopy show that Ca2+ rapidly converts isolated RCK monomers to multimers at alkaline pH. In contrast, the RCK domain at acidic pH remains firmly dimeric regardless of Ca2+ but restores predominantly to multimer or monomer at basic pH with or without Ca2+, respectively. These functional and biochemical analyses correlate the four functional states of the MthK channel with distinct oligomeric states of its RCK domains and indicate that the RCK domains undergo oligomeric conversions in modulating MthK activities.


    Organizational Affiliation

    Structural Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Calcium-gated potassium channel mthK
A
233Methanothermobacter thermautotrophicus (strain ATCC 29096 / DSM 1053 / JCM 10044 / NBRC 100330 / Delta H)Mutation(s): 0 
Gene Names: mthK
Find proteins for O27564 (Methanothermobacter thermautotrophicus (strain ATCC 29096 / DSM 1053 / JCM 10044 / NBRC 100330 / Delta H))
Go to UniProtKB:  O27564
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.23 Å
  • R-Value Free: 0.299 
  • R-Value Work: 0.232 
  • Space Group: H 3 2
Unit Cell:
Length (Å)Angle (°)
a = 165.890α = 90.00
b = 165.890β = 90.00
c = 82.220γ = 120.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
PHASERphasing
ADSCdata collection
REFMACrefinement
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-02-06
    Type: Initial release
  • Version 1.1: 2008-05-01
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Advisory, Derived calculations, Source and taxonomy, Version format compliance