4J7C

KtrAB potassium transporter from Bacillus subtilis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.5 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.258 

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:  

  • 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: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Ktr system potassium uptake protein A
A, B, C, D, E, F, G, H
222Bacillus subtilis (strain 168)Mutation(s): 1 
Gene Names: ktrA (yuaA)
Membrane protein
mpstruct
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))
Go to UniProtKB:  O32080
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Ktr system potassium uptake protein B
I, J, K, L
465Bacillus subtilis (strain 168)Mutation(s): 0 
Gene Names: ktrB (yubG)
Membrane protein
mpstruct
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))
Go to UniProtKB:  O32081
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
K
Query on K

Download SDF File 
Download CCD File 
I, J, K, L
POTASSIUM ION
K
NPYPAHLBTDXSSS-UHFFFAOYSA-N
 Ligand Interaction
ATP
Query on ATP

Download SDF File 
Download CCD File 
A, B, C, D, E, F, G, H
ADENOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O13 P3
ZKHQWZAMYRWXGA-KQYNXXCUSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.5 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.258 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 146.520α = 90.00
b = 140.190β = 105.69
c = 153.930γ = 90.00
Software Package:
Software NamePurpose
SCALAdata scaling
PHASERphasing
DMphasing
PDB_EXTRACTdata extraction
REFMACrefinement
DNAdata collection
XSCALEdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

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