4HZ3

MthK pore crystallized in presence of TBSb


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.192 
  • R-Value Work: 0.173 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

The voltage-dependent gate in MthK potassium channels is located at the selectivity filter.

Posson, D.J.McCoy, J.G.Nimigean, C.M.

(2013) Nat.Struct.Mol.Biol. 20: 159-166

  • DOI: 10.1038/nsmb.2473
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Understanding how ion channels open and close their pores is crucial for comprehending their physiological roles. We used intracellular quaternary ammonium blockers, electrophysiology and X-ray crystallography to locate the voltage-dependent gate in ...

    Understanding how ion channels open and close their pores is crucial for comprehending their physiological roles. We used intracellular quaternary ammonium blockers, electrophysiology and X-ray crystallography to locate the voltage-dependent gate in MthK potassium channels from Methanobacterium thermoautotrophicum. Blockers bind in an aqueous cavity between two putative gates: an intracellular gate and the selectivity filter. Thus, these blockers directly probe gate location--an intracellular gate will prevent binding when closed, whereas a selectivity filter gate will always allow binding. Kinetic analysis of tetrabutylammonium block of single MthK channels combined with X-ray crystallographic analysis of the pore with tetrabutyl antimony unequivocally determined that the voltage-dependent gate, like the C-type inactivation gate in eukaryotic channels, is located at the selectivity filter. State-dependent binding kinetics suggest that MthK inactivation leads to conformational changes within the cavity and intracellular pore entrance.


    Organizational Affiliation

    Department of Anesthesiology, Weill Cornell Medical College, New York, New York, USA. djp2003@med.cornell.edu




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Calcium-gated potassium channel mthK
D, C, A, B, E, F, G, H
91Methanothermobacter thermautotrophicus (strain ATCC 29096 / DSM 1053 / JCM 10044 / NBRC 100330 / Delta H)Mutation(s): 2 
Gene Names: mthK
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Channels: Potassium, Sodium, & Proton Ion-Selective
Protein: 
MthK Potassium channel, Ca++ gated
Find proteins for O27564 (Methanothermobacter thermautotrophicus (strain ATCC 29096 / DSM 1053 / JCM 10044 / NBRC 100330 / Delta H))
Go to UniProtKB:  O27564
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
K
Query on K

Download SDF File 
Download CCD File 
D, E
POTASSIUM ION
K
NPYPAHLBTDXSSS-UHFFFAOYSA-N
 Ligand Interaction
HEZ
Query on HEZ

Download SDF File 
Download CCD File 
A, B, C, D, E, F, G, H
HEXANE-1,6-DIOL
C6 H14 O2
XXMIOPMDWAUFGU-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.192 
  • R-Value Work: 0.173 
  • Space Group: P 1
Unit Cell:
Length (Å)Angle (°)
a = 43.965α = 89.99
b = 63.396β = 89.95
c = 63.311γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
HKL-2000data scaling
PDB_EXTRACTdata extraction
HKL-2000data collection
SCALEPACKdata scaling
REFMACrefinement
HKL-2000data reduction
DENZOdata reduction
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-12-26
    Type: Initial release
  • Version 1.1: 2013-03-06
    Type: Database references