短距離脊柱二面回転は,内在的に乱れたタンパク質の内部摩擦を調節する
Debapriya Das1,2, Lisha Arora1,2, Samrat Mukhopadhyay1,2,3
1Centre for Protein Science, Design and Engineering, Indian Institute of Science Education and Research (IISER) Mohali, Knowledge City, Sector 81, Mohali, SAS Nagar, Punjab 140306, India.
Journal of the American Chemical Society
|January 24, 2022
まとめ
本質的に乱れたタンパク質 (IDP) の内部の摩擦は,溶媒の粘度だけでなく,骨幹二面障壁から生じる. プロリンやグリシンのようなシーケンス固有の残留物は,この摩擦を調節し,タンパク質のダイナミクスに影響を与えます.
科学分野:
- バイオ物理学
- タンパク質ダイナミクス
- 分子 相互作用
背景:
- タンパク質の折りたたみとダイナミクスは,溶媒の粘度と内部摩擦によって影響されます.
- 内部摩擦は,形状の変化に対するポリペプチド鎖の固有の抵抗です.
- 本質的に乱れたタンパク質 (IDP) の内部摩擦の分子起源は不明である.
研究 の 目的:
- IDPの内部摩擦の分子起源を調査する
- 配列特異的な骨幹二面障壁が局所的な内部摩擦を制御することを示すために.
- 内部の摩擦を調節する特定のアミノ酸の役割を分析する.
主な方法:
- サイト指向の光脱極化運動
- ピコ秒時間解像度による光アニソトロピー測定
- 線形粘度依存モデルを用いた二面的なリラックス時間の分析.
主要な成果:
- 局所的な内部摩擦の源として,シーケンスの固有のバックボーン二面障壁を特定した.
- プロリンを含まないセグメントでは内部の摩擦が低く,プロリンを含むセグメントでは内部の摩擦が高く観察された.
- プロリンによってもたらされるトルションの硬さを補うことが示された.
結論:
- IDPの局所的な内部摩擦は,シーケンス固有の二面障壁によって制御される.
- アミノ酸の配列,特にプロリンとグリシンは,内部の摩擦を調節する上で重要な役割を果たします.
- ローカルな内部摩擦を理解することは,折り畳み,結合,組み立てのIDPの行動を理解する鍵です.
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