4QE7: Calcium-gated potassium channel MthK

Open MthK pore structure soaked in 10 mM Ba2+/100 mM Na+. Determined by X-ray diffraction at 2.4 Å resolution. Released 9 Jul 2014.

Method: X-ray diffraction
Resolution: 2.4 Å
Organism: Methanothermobacter thermautotrophicus
Chains: 1
Atoms: 664
Mol. weight: 9.35 kDa
Ligands: BA
Released: 9 Jul 2014

Explore 4QE7 in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

4QE7 contains 3 α-helices and 0 β-strands across 1 chain. Residue ranges use author residue numbering, as in the PDB file, from PDBe. To see them in 3D, choose the Cartoon representation with Secondary structure coloring: helices, sheets and coils get different colors.

Chain A: 3 helices, 0 β-strands

Element	Residues	Length
α-helix	20-42	23
α-helix	46-57	12
α-helix	70-98	29

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Calcium-gated potassium channel MthK	A	protein	81	Methanothermobacter thermautotrophicus	O27564 (AlphaFold model)

Sequence of entity 1 (A), FASTA

>4QE7_1 Calcium-gated potassium channel MthK (chains A)
PATRILLLVLAVIIYGTAGFHFIEGESWTVSLYWTFVTIATVGYGDYSPHTPLGMYFTCT
LIVLGIGTFAVAVERLLEFLI

Ligands and cofactors

ID	Name	Formula	Copies
BA	Barium ion	Ba	3

Primary citation

Ionic interactions of Ba2+ blockades in the MthK K+ channel. Guo, R., Zeng, W., Cui, H. et al. J Gen Physiol (2014) 144:193-200. DOI 10.1085/jgp.201411192 · PubMed

Other PDB entries of the same protein (UniProt O27564 (AlphaFold model), which also has an AlphaFold model), best resolution first:

3LDC 1.45 Å, High resolution open MthK pore structure crystallized in 100 mM K+
3LDD 1.45 Å, High resolution open MthK pore structure crystallized in 100 mM K+ and further soaked in…
6U9T 1.55 Å, Wild-type MthK pore in 50 mM K+
4HYO 1.65 Å, Crystal Structure of MthK Pore
6U9P 1.65 Å, Wild-type MthK pore in ~150 mM K+
2AEF 1.7 Å, Crystal Structures of the MthK RCK Domain in Ca2+ bound form
4HZ3 1.7 Å, MthK pore crystallized in presence of TBSb
3OUS 1.75 Å, MthK channel pore T59A mutant
3R65 1.8 Å, MthK channel pore E92Q mutant
6U9Y 1.8 Å, Wild-type MthK pore in 11 mM K+
4L74 1.84 Å, Ca2+-bound MthK RCK domain at 1.9 Angstrom with single ligand
6U9Z 1.95 Å, Wild-type MthK pore in 6 mM K+

Browse structure collections

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