This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1lnq
From Proteopedia
|
CRYSTAL STRUCTURE OF MTHK AT 3.3 A
Overview
Ion channels exhibit two essential biophysical properties; that is, selective ion conduction, and the ability to gate-open in response to an appropriate stimulus. Two general categories of ion channel gating are defined by the initiating stimulus: ligand binding (neurotransmitter- or second-messenger-gated channels) or membrane voltage (voltage-gated channels). Here we present the structural basis of ligand gating in a K(+) channel that opens in response to intracellular Ca(2+). We have cloned, expressed, analysed electrical properties, and determined the crystal structure of a K(+) channel (MthK) from Methanobacterium thermoautotrophicum in the Ca(2+)-bound, opened state. Eight RCK domains (regulators of K(+) conductance) form a gating ring at the intracellular membrane surface. The gating ring uses the free energy of Ca(2+) binding in a simple manner to perform mechanical work to open the pore.
About this Structure
1LNQ is a Single protein structure of sequence from Methanothermobacter thermautotrophicus with as ligand. The following page contains interesting information on the relation of 1LNQ with [Potassium Channels]. Full crystallographic information is available from OCA.
Reference
Crystal structure and mechanism of a calcium-gated potassium channel., Jiang Y, Lee A, Chen J, Cadene M, Chait BT, MacKinnon R, Nature. 2002 May 30;417(6888):515-22. PMID:12037559
Page seeded by OCA on Thu Feb 21 13:46:39 2008
