マイクロクリスタリンユビキチンに対する炭素NMR共鳴の割り当て
Tatyana I Igumenova1, Ann E McDermott, Kurt W Zilm
1Department of Chemistry, Columbia University, 3000 Broadway MC 3113, New York, New York 10027, USA.
Journal of the American Chemical Society
|May 27, 2004
まとめ
固体NMR 2Dスペクトロスコピーは,ユビキチンにおける炭素化学的シフトを効果的に相関させた. この方法は,アミノ酸側鎖の半分以上のスピンシステムを特定し,サイト固有の割り当てを可能にしました.
科学分野:
- 固体核磁共振 (NMR) スペクトロスコーピーは,固体核磁共振 (NMR) スペクトロスコーピーを用います.
- タンパク質構造の決定
- バイオフィジックス 生物物理学
背景:
- 固体NMRは,非結晶性またはマイクロ結晶性状態のタンパク質構造を分析するために重要である.
- 炭素のバックボーンとサイドチェーンの化学的シフトを相関させることで,詳細な構造情報が得られます.
研究 の 目的:
- マイクロクリスタルのユビキチンにおける炭素化学的シフトを相関させるための固体NMR 2Dスペクトロスコーピーの方法を開発し,適用する.
- 炭素-炭素相関を特定するための磁気化移転の効率を評価する.
主な方法:
- 均一に利用される (13) C, (((15) Nで濃縮されたマイクロクリスタリンユビキチン.
- 高磁場強度 (800MHzの陽子周波数) とマジックアングルサンプルの回転 (20kHz) を採用した.
- ホモ核磁化移転のための20 msの混合時間を持つ二極補助回転共振 (DARR) を適用しました.
主要な成果:
- 細かい炭素線幅 (0.5-0.8ppm) を達成し,詳細なスペクトル分析を可能にしました.
- 温和な単一結合炭素-炭素伝送効率 (~14%) と弱い二結合相関 (~4%) を観測した.
- アミノ酸側鎖の50%以上のスピンシステムを成功裏に特定しました.
結論:
- DARR配列は,固体NMRにおける1結合と2結合の炭素相関を得るために効率的な方法を提供します.
- このアプローチは,他のNMRテクニックを補完して,タンパク質にサイト固有の割り当てを容易にします.
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