Macromolecule Content

• Total Structure Weight: 14.45 kDa 
• Atom Count: 136 
• Residue Count: 136 
• Unique protein chains: 1

1JQ1

POTASSIUM CHANNEL (KCSA) OPEN GATE MODEL

• DOI: 10.2210/pdb1JQ1/pdb

• Classification: MEMBRANE PROTEIN
• Organism(s): Streptomyces lividans
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2001-08-03 Released: 2001-10-03 
• Deposition Author(s): Liu, Y.-S., Sompornpisut, P., Perozo, E.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Submitted: 1 

Literature

Structure of the KcsA channel intracellular gate in the open state.

Liu, Y.S., Sompornpisut, P., Perozo, E.

(2001) Nat Struct Biol 8: 883-887

• PubMed: 11573095 
• DOI: 10.1038/nsb1001-883
• Structures With Same Primary Citation


• PubMed Abstract: 
  

Ion channels catalyze the selective transfer of ions across the membrane in response to a variety of stimuli. These channels gate by controlling the access of ions to a centrally located water-filled pore. The crystal structure of the Streptomyces lividans potassium channel (KcsA) has allowed a molecular exploration of this mechanism. Electron paramagnetic resonance (EPR) studies have uncovered significant conformational changes at the intracellular end of the second transmembrane helix (TM2) upon gating. We have used site-directed spin labeling (SDSL) and EPR spectroscopy in an attempt to quantify the structural rearrangements of the KcsA TM2 bundle underlying the transition from the closed to the open state. Under conditions favoring the closed and open conformations, 10 intersubunit distances were obtained across TM2 segments from tandem dimer constructs. Analysis of these data points to a mechanism in which each TM2 helix tilts away from the permeation pathway, towards the membrane plane, and rotates about its helical axis, supporting a scissoring-type motion with a pivot point near residues 107-108. These movements are accompanied by a large increase in the diameter of the vestibule below the central water-filled cavity.

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Related Citations: 

• Calculation of Rigid Body Conformational Changes Using Restraint-Driven Cartesian Transformations
  Sompornpisut, P., Liu, Y.-S., Perozo, E.
  () To be published --: --

• Structural Rearrangements Underlying K+-Channel Activation Gating
  Perozo, E., Cortes, D.M., Cuello, L.G.
  (1999) Science 285: 73

• The Structure of the Potassium Channel: Molecular Basis of K+ Conduction and Selectivity
  Doyle, D.A., Morais Cabral, J., Pfuetzner, R.A., Kuo, A., Gulbis, J.M., Cohen, S.L., Chait, B.T., Mackinnon, R.
  (1998) Science 280: 69

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Organizational Affiliation: 

Department of Molecular Physiology and Biological Physics, Center for Structural Biology, University of Virginia Health Sciences Center, Charlottesville, Virginia 22906-0011, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
VOLTAGE-GATED POTASSIUM CHANNEL	A, B, C, D	34	Streptomyces lividans	Mutation(s): 1  Gene Names: kcsA, skc1
Find proteins for P0A334 (Streptomyces lividans) Go to UniProtKB:  P0A334

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Submitted: 1 
• OLDERADO: 1JQ1 Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2001-08-03 
• Released Date: 2001-10-03 
Deposition Author(s): Liu, Y.-S., Sompornpisut, P., Perozo, E.

Revision History 

• Version 1.0: 2001-10-03
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance