8CTU

Crystal structure of a K+ selective NaK mutant (NaK2K) at Room temperature

• PDB DOI: https://doi.org/10.2210/pdb8CTU/pdb

• Classification: MEMBRANE PROTEIN
• Organism(s): Bacillus cereus m1550
• Expression System: Escherichia coli
• Mutation(s): No 
• Membrane Protein: Yes  PDBTMMemProtMD


• Deposited: 2022-05-16 Released: 2023-06-14 
• Deposition Author(s): Lee, B., White, K.I., Socolich, M.A., Klureza, M.A., Henning, R., Srajer, V., Ranganathan, R., Hekstra, D.
• Funding Organization(s): National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS), National Institutes of Health/Eunice Kennedy Shriver National Institute of Child Health & Human Development (NIH/NICHD), Department of Energy (DOE, United States), Kinship Foundation, New York Community Trust

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.65 Å
• R-Value Free: 0.179 
• R-Value Work: 0.163 
• R-Value Observed: 0.164 

Literature

Direct visualization of electric field-stimulated ion conduction in a potassium channel

Lee, B., White, K.I., Socolich, M.A., Klureza, M.A., Henning, R., Srajer, V., Ranganathan, R., Hekstra, D.

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 (software)

Biological Assembly Evidence: assay for oligomerization

Biological Assembly 2  

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

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 22.71 kDa 
• Atom Count: 1,924 
• Modelled Residue Count: 191 
• Deposited Residue Count: 192 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Potassium channel protein	A, B	96	Bacillus cereus m1550	Mutation(s): 0  Gene Names: bcere0011_5790 Membrane Entity: Yes
UniProt
Find proteins for Q81HW2 (Bacillus cereus (strain ATCC 14579 / DSM 31 / CCUG 7414 / JCM 2152 / NBRC 15305 / NCIMB 9373 / NCTC 2599 / NRRL B-3711)) Explore Q81HW2  Go to UniProtKB:  Q81HW2

Oligosaccharides

Help

Entity ID: 2
Molecule	Chains	Length	2D Diagram	Glycosylation	3D Interactions
alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose	C	2		N/A
Glycosylation Resources
GlyTouCan:  G07411ON GlyCosmos:  G07411ON

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GAL	I [auth B]	beta-D-galactopyranose C6 H12 O6 WQZGKKKJIJFFOK-FPRJBGLDSA-N
MPD	D [auth A], J [auth B], K [auth B], L [auth B], M [auth B]	(4S)-2-METHYL-2,4-PENTANEDIOL C6 H14 O2 SVTBMSDMJJWYQN-YFKPBYRVSA-N
K (Subject of Investigation/LOI)	E [auth A], F [auth A], G [auth A], H [auth A], N [auth B], O [auth B], P [auth B], Q [auth B]	POTASSIUM ION K NPYPAHLBTDXSSS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.65 Å
• R-Value Free: 0.179 
• R-Value Work: 0.163 
• R-Value Observed: 0.164 
• Space Group: I 4

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 68.914	α = 90
b = 68.914	β = 90
c = 90.324	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
HKL-2000	data reduction
HKL-2000	data scaling
PHENIX	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2023-06-14 
Deposition Author(s): Lee, B., White, K.I., Socolich, M.A., Klureza, M.A., Henning, R., Srajer, V., Ranganathan, R., Hekstra, D.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	RO1GM12345
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	RO1GM141697
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	P41GM118217
National Institutes of Health/Eunice Kennedy Shriver National Institute of Child Health & Human Development (NIH/NICHD)	United States	DP2OD028805
Department of Energy (DOE, United States)	United States	DE-AC02-06CH11357
Department of Energy (DOE, United States)	United States	DE-AC02-76SF00515
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	P41GM103393
Kinship Foundation	United States	SSP-2018-3240
New York Community Trust	United States	338034

Revision History  

• Version 1.0: 2023-06-14
  Type: Initial release
  
• Version 1.1: 2024-04-03
  Changes: Data collection, Refinement description