15N R2/R1 リラクゼーション・リフレーンズの分子サイズ,形状,および結合ベクトルの方向性に対する影響は,散らばった距離のリフレーンスを使ってNMRタンパク質構造の決定のためのNMRタンパク質構造の決定です
Yaroslav Ryabov1, Charles D Schwieters, G Marius Clore
1Division of Computational Bioscience, Building 12A, Center for Information Technology, National Institutes of Health, Bethesda, Maryland 20892-5624, USA.
Journal of the American Chemical Society
|April 6, 2011
まとめ
核磁共振 (NMR) のリラクゼーションデータ,特に (15) N R(2) / R(1) の拘束装置は,タンパク質構造の計算を大幅に改善します. これらの制限は,限られた距離情報がある場合にタンパク質の折り畳みを決定するのに特に有用です.
科学分野:
- 構造生物学 構造生物学とは
- バイオフィジックス 生物物理学
- 核磁共振 (NMR) スペクトロスコピー
背景:
- (15) N R(2) / R(1) 値を含むNMRリラクゼーションデータは,分子形状,サイズ,結合ベクトルの方向性についての洞察を提供します.
- これらのリラクゼーションパラメータは,事前の仮定なしに,NMR構造計算に直接統合することができます.
- わずかな距離の制限は,しばしばタンパク質構造の決定の精度を制限します.
研究 の 目的:
- (15) N R(2) / R(1) のリラクゼーション制限の有用性をNMR構造計算で評価するために,特に距離制限が希少である場合.
- 異なるサイズのタンパク質における座標精度に対するこれらの制約の影響を実証する.
主な方法:
- (15) N R(2) / R(1) のリラクゼーションデータを制限としてNMR構造計算に組み込む.
- 3つのタンパク質:GB3 (56残留物),ウビキチン (76残留物),および酵素IのN末端領域 (EIN,249残留物) でこの方法を試験する.
- バックボーン水素結合拘束装置と稀な核オーバーハウザー効果 (NOE) 拘束装置をリラクゼーションデータと併用して利用する.
主要な成果:
- (15) NMR構造計算における座標精度を大幅に向上させた.
- GB3とユビキチンの正確な構造は,バックボーン水素結合と (15) N R(2) / R(1) の拘束装置のみを使用して達成されました.
- より大きなEINタンパク質のグローバル折り畳みは,15N R(2) / R(1) データと組み合わせた稀なNOE制限を使用して決定されました.
結論:
- (15) N R (((2)/R ((1)) のリラクゼーション拘束は,特に距離情報が限られている場合に,NMR構造の決定を改善するために非常に価値があります.
- このアプローチは,より大きく,より複雑なシステムを含むタンパク質の,近似的なグローバルフォールドの決定の実現可能性を高めます.
- この発見は,スペクトルの複雑さがNOEの割り当てとカバーを制限するNMR研究にとって実用的な意味を持つ.
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