› 3iga

X-ray diffraction
2.75Å resolution

Potassium Channel KcsA-Fab complex in Li+ and K+

Released:
DOI: 10.2210/pdb3iga/pdb
PDB entry 3iga coloured by chain, front view.
PDB entry 3iga coloured by chain, side view.
PDB entry 3iga coloured by chain, top view.
Source organisms:
Primary publication:
Mechanism of potassium-channel selectivity revealed by Na(+) and Li(+) binding sites within the KcsA pore.
Thompson AN, Kim I, Panosian TD, Iverson TM, Allen TW, Nimigean CM
Nat Struct Mol Biol 16 1317-24 (2009)
PMID: 19946269

Function and Biology Details

Biochemical function:
  • not assigned
Biological process:
  • not assigned
Cellular component:
  • not assigned
Sequence domains:

Structure analysis Details

Assembly composition:
hetero dodecamer (preferred)
Assembly name:
PDBe Complex ID:
PDB-CPX-209470 (preferred)
Entry contents:
3 distinct polypeptide molecules
Macromolecules (3 distinct):
Antibody Fab Fragment heavy chain Chain: A
Molecule details ›
Chain: A
Length: 219 amino acids
Theoretical weight: 23.41 KDa
Source organism: Mus musculus
Structure domains: Immunoglobulins
Antibody Fab fragment light chain Chain: B
Molecule details ›
Chain: B
Length: 212 amino acids
Theoretical weight: 23.44 KDa
Source organism: Mus musculus
Structure domains: Immunoglobulins
pH-gated potassium channel KcsA Chain: C
Molecule details ›
Chain: C
Length: 124 amino acids
Theoretical weight: 13.21 KDa
Source organism: Streptomyces lividans
Expression system: Escherichia coli
UniProt:
  • Canonical: P0A334 (Residues: 1-124; Coverage: 78%)
Gene names: kcsA, skc1
Sequence domains: Ion channel
Structure domains: Helix Hairpins

Ligands and Environments

2 bound ligands:
Ligand NI 1 x NI
Ligand DGA 1 x DGA
No modified residues

Experiments and Validation Details

Entry percentile scores
X-ray source: APS BEAMLINE 21-ID-G
Spacegroup: I4
Unit cell:
a: 155.799Å b: 155.799Å c: 75.775Å
α: 90° β: 90° γ: 90°
R-values:
R R work R free
0.242 0.242 0.273
Expression system: Escherichia coli

Quick links

Citations

20 review citations

Structure of potassium channels.
Kuang et al. (2015)
19 more

3 mentions without citation

Mechanism of potassium-channel selectivity revealed by Na(+) and Li(+) binding sites within the KcsA pore.
Thompson et al. (2009)
2 more