3G6B

Crystal structure of a Soluble Chemoreceptor from Thermotoga maritima Asn217Ile mutant

3G6B の概要

• エントリーDOI: 10.2210/pdb3g6b/pdb
• 関連するPDBエントリー: 3G67
• 分子名称: Methyl-accepting chemotaxis protein (2 entities in total)
• 機能のキーワード: four-helix bundle, methyl-accepting chemotaxis protein, signaling protein
• 由来する生物種: Thermotoga maritima
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 48266.64

構造登録者

Pollard, A.M.,Bilwes, A.M.,Crane, B.R. (登録日: 2009-02-06, 公開日: 2009-07-28, 最終更新日: 2024-02-21)

主引用文献

Pollard, A.M.,Bilwes, A.M.,Crane, B.R.
The structure of a soluble chemoreceptor suggests a mechanism for propagating conformational signals.
Biochemistry, 48:1936-1944, 2009

PubMed Abstract: Transmembrane chemoreceptors, also known as methyl-accepting chemotaxis proteins (MCPs), translate extracellular signals into intracellular responses in the bacterial chemotaxis system. MCP ligand binding domains control the activity of the CheA kinase, situated approximately 200 A away, across the cytoplasmic membrane. The 2.17 A resolution crystal structure of a Thermotoga maritima soluble receptor (Tm14) reveals distortions in its dimeric four-helix bundle that provide insight into the conformational states available to MCPs for propagating signals. A bulge in one helix generates asymmetry between subunits that displaces the kinase-interacting tip, which resides more than 100 A away. The maximum bundle distortion maps to the adaptation region of transmembrane MCPs where reversible methylation of acidic residues tunes receptor activity. Minor alterations in coiled-coil packing geometry translate the bulge distortion to a >25 A movement of the tip relative to the bundle stalks. The Tm14 structure discloses how alterations in local helical structure, which could be induced by changes in methylation state and/or by conformational signals from membrane proximal regions, can reposition a remote domain that interacts with the CheA kinase.

PubMed: 19149470
DOI: 10.1021/bi801727m

実験手法

X-RAY DIFFRACTION (3 Å)