動的に駆動されたアロステリックシステムにおける溶媒エントロピーの機能的役割と金属結合の適合エントロピーの役割
Daiana A Capdevila1, Katherine A Edmonds1, Gregory C Campanello1
1Department of Chemistry , Indiana University , Bloomington , Indiana 47405-7102 United States.
Journal of the American Chemical Society
|June 29, 2018
まとめ
アロステリーは タンパク質のダイナミクスと 周囲の溶媒の分子を 含みます この研究は,CzrA変異体におけるタンパク質動態の変化が溶媒エントロピーに有意な影響を及ぼし,アロステル調節に影響することを明らかにしています.
科学分野:
- 生物化学
- 分子生物学
- 構造生物学
背景:
- アロステリーは,ある部位でのリガンド結合が別の部位に影響を与える生物学的システムにおける重要な調節メカニズムである.
- アロステル調節の物理的基礎,特に動的に誘導されるアロステル調節は完全に理解されていません.
- タンパク質ダイナミクスと溶媒エントロピーのアロステル調節への貢献は,活発な研究分野である.
研究 の 目的:
- アロステル調節におけるタンパク質動力学と溶媒エントロピーの相互作用を調査する.
- CzrAにおけるZnによるDNA結合のアロステリック阻害に対する溶媒エントロピーと残基特異的ダイナミクスの相対的貢献を解剖する.
- ダイナミックに駆動されたアロステリーにおける水分子の役割を理解する.
主な方法:
- 新しい結晶構造を得るためのX線結晶学.
- 熱力学的な変化を評価するための熱量測定試験
- 様々な時間スケールと温度で残留物特有のダイナミクス研究
- アロステリック障害のCrA変異体の分析
主要な成果:
- CzrA変異体における非原生残留特異動態が観察された.
- これらのダイナミクスは,溶媒エントロピーの有意な混乱と関連していました.
- これらの溶媒エントロピーの変化は,結晶構造だけで予測できない.
- CzrAにおけるZnによるDNA結合のアロステリック阻害を調査した.
結論:
- アロステリーの機能的動態は,タンパク質残基を超えて,表面水分子を含みます.
- タンパク質の内部運動におけるリガンド媒介による干渉は溶媒のエントロピーに影響する.
- アロステリック調節は,大きな構造的変化だけでなく,形状全体を含みます.
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