2NLJ

Potassium Channel KcsA(M96V)-Fab complex in KCl

2NLJ の概要

• エントリーDOI: 10.2210/pdb2nlj/pdb
• 関連するPDBエントリー: 2itc 2itd
• 分子名称: antibody Fab fragment light chain, antibody Fab fragment heavy chain, Voltage-gated potassium channel, ... (6 entities in total)
• 機能のキーワード: voltage-gated channel, transmembrane, ionic channel, ion transport, k channel, protein-antibody fab complex, membrane protein
• 由来する生物種: Streptomyces lividans; 詳細
• 細胞内の位置: Cell membrane; Multi-pass membrane protein: P0A334
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 60768.81

構造登録者

Lockless, S.W.,Zhou, M.,MacKinnon, R. (登録日: 2006-10-20, 公開日: 2007-05-15, 最終更新日: 2024-10-16)

主引用文献

Lockless, S.W.,Zhou, M.,Mackinnon, R.
Structural and Thermodynamic Properties of Selective Ion Binding in a K(+) Channel.
Plos Biol., 5:e121-e121, 2007

PubMed Abstract: Thermodynamic measurements of ion binding to the Streptomyces lividans K(+) channel were carried out using isothermal titration calorimetry, whereas atomic structures of ion-bound and ion-free conformations of the channel were characterized by x-ray crystallography. Here we use these assays to show that the ion radius dependence of selectivity stems from the channel's recognition of ion size (i.e., volume) rather than charge density. Ion size recognition is a function of the channel's ability to adopt a very specific conductive structure with larger ions (K(+), Rb(+), Cs(+), and Ba(2+)) bound and not with smaller ions (Na(+), Mg(2+), and Ca(2+)). The formation of the conductive structure involves selectivity filter atoms that are in direct contact with bound ions as well as protein atoms surrounding the selectivity filter up to a distance of 15 A from the ions. We conclude that ion selectivity in a K(+) channel is a property of size-matched ion binding sites created by the protein structure.

PubMed: 17472437
DOI: 10.1371/journal.pbio.0050121

実験手法

X-RAY DIFFRACTION (2.52 Å)