1XL6

Intermediate gating structure 2 of the inwardly rectifying K+ channel KirBac3.1

• PDB DOI: https://doi.org/10.2210/pdb1XL6/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: 2.85 Å
• R-Value Free: 0.310 
• R-Value Work: 0.270 

Re-refinement Note

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

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: 68.07 kDa 
• Atom Count: 4,734 
• Modelled Residue Count: 582 
• 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 D9N164 (Magnetospirillum magnetotacticum) Explore D9N164  Go to UniProtKB:  D9N164

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SPM	K [auth B]	SPERMINE C10 H26 N4 PFNFFQXMRSDOHW-UHFFFAOYSA-N
K	C [auth A], D [auth A], E [auth A], F [auth A], G [auth A], H [auth A], J [auth B]	POTASSIUM ION K NPYPAHLBTDXSSS-UHFFFAOYSA-N
MG	I [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.85 Å
• R-Value Free: 0.310 
• R-Value Work: 0.270 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 105.756	α = 90
b = 107.532	β = 90
c = 89.654	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