6OLY

Full-length MthK channel at 3.1 angstrom resolution

Summary for 6OLY

• Entry DOI: 10.2210/pdb6oly/pdb
• Descriptor: Calcium-gated potassium channel MthK, CALCIUM ION (3 entities in total)
• Functional Keywords: potassium channel, calcium-binding, rck domain, rossmann fold, membrane protein
• Biological source: Methanothermobacter thermautotrophicus
• Total number of polymer chains: 4
• Total formula weight: 155591.83

Authors

Rothberg, B.S. (deposition date: 2019-04-17, release date: 2019-12-11, Last modification date: 2023-10-11)

Primary citation

Kopec, W.,Rothberg, B.S.,de Groot, B.L.
Molecular mechanism of a potassium channel gating through activation gate-selectivity filter coupling.
Nat Commun, 10:5366-5366, 2019

PubMed Abstract: Potassium channels are presumed to have two allosterically coupled gates, the activation gate and the selectivity filter gate, that control channel opening, closing, and inactivation. However, the molecular mechanism of how these gates regulate Kion flow through the channel remains poorly understood. An activation process, occurring at the selectivity filter, has been recently proposed for several potassium channels. Here, we use X-ray crystallography and extensive molecular dynamics simulations, to study ion permeation through a potassium channel MthK, for various opening levels of both gates. We find that the channel conductance is controlled at the selectivity filter, whose conformation depends on the activation gate. The crosstalk between the gates is mediated through a collective motion of channel helices, involving hydrophobic contacts between an isoleucine and a conserved threonine in the selectivity filter. We propose a gating model of selectivity filter-activated potassium channels, including pharmacologically relevant two-pore domain (K2P) and big potassium (BK) channels.

PubMed: 31772184
DOI: 10.1038/s41467-019-13227-w

Experimental method

X-RAY DIFFRACTION (3.112 Å)