3RBZ

MthK channel, Ca2+-bound

• PDB DOI: https://doi.org/10.2210/pdb3RBZ/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Methanothermobacter thermautotrophicus str. Delta H
• Expression System: Escherichia coli
• Mutation(s): Yes 
• Membrane Protein: Yes  PDBTMmpstruc


• Deposited: 2011-03-30 Released: 2011-10-12 
• Deposition Author(s): Taylor, A.B., Parfenova, L.V., Rothberg, B.S.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.40 Å
• R-Value Free: 0.288 
• R-Value Work: 0.257 
• R-Value Observed: 0.259 

Literature

Structures of multiple Ca2+-binding sites in a K+ channel RCK domain

Pau, V.P., Smith, F.J., Taylor, A.B., Samakai, E., Callaghan, M.M., Abarca-Heidemann, K., Parfenova, L.V., Hart, P.J., Rothberg, B.S.

(2011) Proc Natl Acad Sci U S A 

Biological Assembly 1  

Global Symmetry: Dihedral - D4  (Explore in 3D)
Global Stoichiometry: Homo 8-mer - A8 

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

Macromolecule Content

• Total Structure Weight: 151.41 kDa 
• Atom Count: 8,153 
• Modelled Residue Count: 1,141 
• Deposited Residue Count: 1,360 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Calcium-gated potassium channel mthK	A, B, C, D	340	Methanothermobacter thermautotrophicus str. Delta H	Mutation(s): 4  Gene Names: mthK, MTH_1520 Membrane Entity: Yes
UniProt
Find proteins for O27564 (Methanothermobacter thermautotrophicus (strain ATCC 29096 / DSM 1053 / JCM 10044 / NBRC 100330 / Delta H)) Explore O27564  Go to UniProtKB:  O27564

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CA	E [auth A], F [auth A], G [auth A], H [auth B], I [auth B], J [auth B], K [auth C], L [auth C], M [auth C], N [auth D], O [auth D], P [auth D]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.40 Å
• R-Value Free: 0.288 
• R-Value Work: 0.257 
• R-Value Observed: 0.259 
• Space Group: P 6₁ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 138.558	α = 90
b = 138.558	β = 90
c = 371.62	γ = 120

Software Package:

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

Structure Validation

Entry History 

Deposition Data

• Released Date: 2011-10-12 
Deposition Author(s): Taylor, A.B., Parfenova, L.V., Rothberg, B.S.

Revision History  

• Version 1.0: 2011-10-12
  Type: Initial release
  
• Version 1.1: 2023-09-13
  Changes: Data collection, Database references, Derived calculations, Refinement description