1XL4

Intermediate gating structure 1 of the inwardly rectifying K+ channel KirBac3.1

• PDB DOI: https://doi.org/10.2210/pdb1XL4/pdb

• Classification: METAL TRANSPORT
• Organism(s): Paramagnetospirillum magnetotacticum
• Expression System: Escherichia coli
• Mutation(s): No 
• Membrane Protein: Yes  PDBTMMemProtMDmpstruc


• Deposited: 2004-09-30 Released: 2004-12-07 
• Deposition Author(s): Gulbis, J.M., Kuo, A., Smith, B., Doyle, D.A., Edwards, A., Arrowsmith, C., Sundstrom, M.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.60 Å
• R-Value Free: 0.253 
• R-Value Work: 0.226 

Starting Model: experimental

Re-refinement Note

A newer entry is available that reflects an alternative modeling of the original data: 2WLJ

Literature

Two intermediate gating state crystal structures of the KirBac3.1 K+ channel

Gulbis, J.M., Kuo, A., Smith, B., Doyle, D.A., Edwards, A., Arrowsmith, C., Sundstrom, M.

To be published.

Biological Assembly 1  

Global Symmetry: Cyclic - C4  (Explore in 3D)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 1 assigned by authors and generated by PISA,PQS (software)

Macromolecule Content

• Total Structure Weight: 67.79 kDa 
• Atom Count: 4,673 
• Modelled Residue Count: 566 
• Deposited Residue Count: 602 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Inward rectifier potassium channel	A, B	301	Paramagnetospirillum magnetotacticum	Mutation(s): 0  Membrane Entity: Yes
UniProt
Find proteins for Q2W6R1 (Paramagnetospirillum magneticum (strain ATCC 700264 / AMB-1)) Explore Q2W6R1  Go to UniProtKB:  Q2W6R1

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
K	C [auth A], D [auth A], E [auth A], F [auth A], G [auth A]	POTASSIUM ION K NPYPAHLBTDXSSS-UHFFFAOYSA-N
MG	H [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.60 Å
• R-Value Free: 0.253 
• R-Value Work: 0.226 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 105.627	α = 90
b = 109.385	β = 90
c = 88.786	γ = 90

Software Package:

Software Name	Purpose
MOSFLM	data reduction
SCALA	data scaling
CNS	refinement
X-PLOR	refinement
CCP4	data scaling
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2004-12-07 
Deposition Author(s): Gulbis, J.M., Kuo, A., Smith, B., Doyle, D.A., Edwards, A., Arrowsmith, C., Sundstrom, M.

Revision History  

• Version 1.0: 2004-12-07
  Type: Initial release
  
• Version 1.1: 2008-04-30
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Derived calculations, Version format compliance
• Version 1.3: 2023-10-25
  Changes: Data collection, Database references, Derived calculations, Refinement description