1F6G

POTASSIUM CHANNEL (KCSA) FULL-LENGTH FOLD

1F6G の概要

• エントリーDOI: 10.2210/pdb1f6g/pdb
• 関連するPDBエントリー: 1bl8
• 分子名称: VOLTAGE-GATED POTASSIUM CHANNEL (1 entity in total)
• 機能のキーワード: potassium channel, integral membrane protein, cytoplasmic domains, proton transport, membrane protein
• 由来する生物種: Streptomyces lividans
• 細胞内の位置: Cell membrane; Multi-pass membrane protein: P0A334
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 70141.50

構造登録者

Cortes, D.M.,Perozo, E. (登録日: 2000-06-21, 公開日: 2001-02-21, 最終更新日: 2024-05-22)

主引用文献

Cortes, D.M.,Cuello, L.G.,Perozo, E.
Molecular architecture of full-length KcsA: role of cytoplasmic domains in ion permeation and activation gating.
J.Gen.Physiol., 117:165-180, 2001

PubMed Abstract: The molecular architecture of the NH(2) and COOH termini of the prokaryotic potassium channel KcsA has been determined using site-directed spin-labeling methods and paramagnetic resonance EPR spectroscopy. Cysteine mutants were generated (residues 5-24 and 121-160) and spin labeled, and the X-band CW EPR spectra were obtained from liposome-reconstituted channels at room temperature. Data on probe mobility (DeltaHo(-1)), accessibility parameters (PiO(2) and PiNiEdda), and inter-subunit spin-spin interaction (Omega) were used as structural constraints to build a three-dimensional folding model of these cytoplasmic domains from a set of simulated annealing and restrained molecular dynamics runs. 32 backbone structures were generated and averaged using fourfold symmetry, and a final mean structure was obtained from the eight lowest energy runs. Based on the present data, together with information from the KcsA crystal structure, a model for the three-dimensional fold of full-length KcsA was constructed. In this model, the NH(2) terminus of KcsA forms an alpha-helix anchored at the membrane-water interface, while the COOH terminus forms a right-handed four-helix bundle that extend some 40-50 A towards the cytoplasm. Functional analysis of COOH-terminal deletion constructs suggest that, while the COOH terminus does not play a substantial role in determining ion permeation properties, it exerts a modulatory role in the pH-dependent gating mechanism.

PubMed: 11158168
DOI: 10.1085/jgp.117.2.165

実験手法

SOLUTION NMR