Macromolecule Content

• Total Structure Weight: 3.39 kDa 
• Atom Count: 240 
• Residue Count: 28 
• Unique protein chains: 1

2K44

Solution structure of a K+-channel voltage-sensor paddle domain

• DOI: 10.2210/pdb2K44/pdb

• Classification: MEMBRANE PROTEIN
• Mutation(s): No 


• Deposited: 2008-05-28 Released: 2009-06-02 
• Deposition Author(s): Unnerstale, S., Lind, J., Papadopoulos, E., Maler, L.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 30 
• Selection Criteria: target function 

Literature

Solution structure of the HsapBK K+-channel voltage-sensor paddle sequence

Unnerstale, S., Lind, J., Papadopoulos, E., Maler, L.

(2009) Biochemistry 

• PubMed: 19456106 
• DOI: 10.1021/bi9004599
• Primary Citation of Related Structures:  
  2K44


• PubMed Abstract: 
  

Voltage-gated potassium channels open and close in response to changes in the membrane potential. In this study, we have determined the NMR solution structure of the putative S3b-S4 voltage-sensor paddle fragment, the part that moves to mediate voltage gating, of the HsapBK potassium channel in dodecylphosphocholine (DPC) micelles. This paper presents the first structure of the S3b-S4 fragment from a BK channel. Diffusion coefficients as determined from PFG NMR experiments showed that a well-defined complex between the peptide and DPC molecules was formed. The structure reveals a helix-turn-helix motif, which is in agreement with crystal structures of other voltage-gated potassium channels, thus indicating that it is feasible to study the isolated fragment. The paddle motifs generally contain several basic residues, implicated in the gating. The critical Arg residues in this structure all reside on the surface, which is in agreement with crystal structures of K(v) channels. Similarities in the structure of the S3b-S4 fragment in BK and K(v) channels as well as important differences are seen, which may be important for explaining the details in paddle movement within a bilayer.

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Organizational Affiliation: 

Department of Biochemistry and Biophysics, Center for Biomembrane Research, The Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
K+-channel voltage-sensor paddle domain of Calcium-activated potassium channel subunit alpha-1	A	28	N/A	Mutation(s): 0
Find proteins for Q12791 (Homo sapiens) Explore Q12791  Go to UniProtKB:  Q12791
NIH Common Fund Data Resources
PHAROS:  Q12791 GTEx:  ENSG00000156113

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 30 
• Selection Criteria: target function 
• OLDERADO: 2K44 Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2008-05-28 
• Released Date: 2009-06-02 
Deposition Author(s): Unnerstale, S., Lind, J., Papadopoulos, E., Maler, L.

Revision History 

• Version 1.0: 2009-06-02
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance