4J7C

KtrAB potassium transporter from Bacillus subtilis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.50 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.258 
  • R-Value Observed: 0.259 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

The structure of the KtrAB potassium transporter

Vieira-Pires, R.S.Szollosi, A.Morais-Cabral, J.H.

(2013) Nature 496: 323-328

  • DOI: 10.1038/nature12055
  • Primary Citation of Related Structures:  
    4J7C, 4J90, 4J91

  • PubMed Abstract: 
  • In bacteria, archaea, fungi and plants the Trk, Ktr and HKT ion transporters are key components of osmotic regulation, pH homeostasis and resistance to drought and high salinity. These ion transporters are functionally diverse: they can function as N ...

    In bacteria, archaea, fungi and plants the Trk, Ktr and HKT ion transporters are key components of osmotic regulation, pH homeostasis and resistance to drought and high salinity. These ion transporters are functionally diverse: they can function as Na(+) or K(+) channels and possibly as cation/K(+) symporters. They are closely related to potassium channels both at the level of the membrane protein and at the level of the cytosolic regulatory domains. Here we describe the crystal structure of a Ktr K(+) transporter, the KtrAB complex from Bacillus subtilis. The structure shows the dimeric membrane protein KtrB assembled with a cytosolic octameric KtrA ring bound to ATP, an activating ligand. A comparison between the structure of KtrAB-ATP and the structures of the isolated full-length KtrA protein with ATP or ADP reveals a ligand-dependent conformational change in the octameric ring, raising new ideas about the mechanism of activation in these transporters.


    Organizational Affiliation

    Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, Porto 4150-180, Portugal.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Ktr system potassium uptake protein AABCDEFGH222Bacillus subtilis subsp. subtilis str. 168Mutation(s): 1 
Gene Names: ktrAyuaABSU31090
Membrane protein
Mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Superfamily of K+ Transporters (SKT proteins)
Protein: 
KtrAB potassium ion transporter
Find proteins for O32080 (Bacillus subtilis (strain 168))
Explore O32080 
Go to UniProtKB:  O32080
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Ktr system potassium uptake protein BIJKL465Bacillus subtilis subsp. subtilis str. 168Mutation(s): 0 
Gene Names: ktrByubGBSU31100
Membrane protein
Mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Superfamily of K+ Transporters (SKT proteins)
Protein: 
KtrAB potassium ion transporter
Find proteins for O32081 (Bacillus subtilis (strain 168))
Explore O32081 
Go to UniProtKB:  O32081
Protein Feature View
Expand
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ATP
Query on ATP

Download CCD File 
A, B, C, D, E, F, G, H
ADENOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O13 P3
ZKHQWZAMYRWXGA-KQYNXXCUSA-N
 Ligand Interaction
K
Query on K

Download CCD File 
I, J, K, L
POTASSIUM ION
K
NPYPAHLBTDXSSS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.50 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.258 
  • R-Value Observed: 0.259 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 146.52α = 90
b = 140.19β = 105.69
c = 153.93γ = 90
Software Package:
Software NamePurpose
SCALAdata scaling
PHASERphasing
DMphasing
REFMACrefinement
PDB_EXTRACTdata extraction
DNAdata collection
XSCALEdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-04-17
    Type: Initial release
  • Version 1.1: 2013-08-07
    Changes: Database references