2IH3

Ion selectivity in a semi-synthetic K+ channel locked in the conductive conformation


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.72 Å
  • R-Value Free: 0.242 
  • R-Value Work: 0.233 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Ion Selectivity in a Semisynthetic K+ Channel Locked in the Conductive Conformation.

Valiyaveetil, F.I.Leonetti, M.Muir, T.W.Mackinnon, R.

(2006) Science 314: 1004-1007

  • DOI: 10.1126/science.1133415
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Potassium channels are K+-selective protein pores in cell membrane. The selectivity filter is the functional unit that allows K+ channels to distinguish potassium (K+) and sodium (Na+) ions. The filter's structure depends on whether K+ or Na+ ions ar ...

    Potassium channels are K+-selective protein pores in cell membrane. The selectivity filter is the functional unit that allows K+ channels to distinguish potassium (K+) and sodium (Na+) ions. The filter's structure depends on whether K+ or Na+ ions are bound inside it. We synthesized a K+ channel containing the d-enantiomer of alanine in place of a conserved glycine and found by x-ray crystallography that its filter maintains the K+ (conductive) structure in the presence of Na+ and very low concentrations of K+. This channel conducts Na+ in the absence of K+ but not in the presence of K+. These findings demonstrate that the ability of the channel to adapt its structure differently to K+ and Na+ is a fundamental aspect of ion selectivity, as is the ability of multiple K+ ions to compete effectively with Na+ for the conductive filter.


    Organizational Affiliation

    Laboratories of Molecular Neurobiology and Biophysics and Synthetic Protein Chemistry, Rockefeller University and Howard Hughes Medical Institute, 1230 York Avenue, New York, NY 10021, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
FAB Heavy Chain
A
219N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
FAB Light Chain
B
212N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Voltage-gated potassium channel
C
122Streptomyces lividansMutation(s): 2 
Gene Names: kcsA (skc1)
Find proteins for P0A334 (Streptomyces lividans)
Go to UniProtKB:  P0A334
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
K
Query on K

Download SDF File 
Download CCD File 
C
POTASSIUM ION
K
NPYPAHLBTDXSSS-UHFFFAOYSA-N
 Ligand Interaction
1EM
Query on 1EM

Download SDF File 
Download CCD File 
C
(1S)-2-HYDROXY-1-[(NONANOYLOXY)METHYL]ETHYL MYRISTATE
C26 H50 O5
IHUWMVGHYXVIRN-DEOSSOPVSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
DAL
Query on DAL
C
D-PEPTIDE LINKINGC3 H7 N O2

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Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.72 Å
  • R-Value Free: 0.242 
  • R-Value Work: 0.233 
  • Space Group: I 4
Unit Cell:
Length (Å)Angle (°)
a = 155.724α = 90.00
b = 155.724β = 90.00
c = 75.741γ = 90.00
Software Package:
Software NamePurpose
PDB_EXTRACTdata extraction
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling
CBASSdata collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-11-21
    Type: Initial release
  • Version 1.1: 2008-05-01
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance
  • Version 1.3: 2011-11-16
    Type: Atomic model