スキャラカップルプロトンを有するシステムにおける表面横断リラクゼーション率
Bikash Baishya1, Takuya F Segawa, Geoffrey Bodenhausen
1Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne, BCH, 1015 Lausanne, Switzerland. bikash.baishya@epfl.ch
Journal of the American Chemical Society
|December 3, 2009
まとめ
この研究は,スカラー結合によって引き起こされるエコー変調を消し去ることで,陽子のリラックス率を測定する課題を克服しています. この方法は,サイクロスポリンAのような複雑な分子における横断リラクゼーション率の正確な決定を可能にします.
科学分野:
- 磁気共振スペクトロスコピー 磁気共振スペクトロスコピー
- バイオ物理化学 バイオ物理化学
- 核磁気共鳴法による核磁気共鳴法
背景:
- 同核スカラー結合は,スピンエコーを調節し,横断リラクゼーション率の測定を複雑にします.
- 以前の方法は,孤立したスピンに限定され,複雑な分子分析を制限していました.
- 炭素-13 ((13) C) または窒素-15 ((15) N) とスケーラカップリングされた陽子の同位体濃縮は課題を提示します.
研究 の 目的:
- ホモ核スカラー結合の存在下における陽子の表面的横断リラクゼーション速度を測定する方法を開発する.
- 孤立したスピンに限定された以前の研究の限界を克服するために.
- (1) サイクロスポリンA (CsA) の横断リラクゼーション速度を正確に決定するために.
主な方法:
- 再フォーカスのパルスを利用して,エコー・モジュレーションを消す.
- 表面的な (1) H横断リラクゼーション率を測定する.
- サイクロスポリンAのバックボーンとサイドチェーン陽子にこの方法を適用する.
主要な成果:
- ホモ核スカラー結合から生じるエコー調節を成功裏に消した.
- サイクロスポリンAの陽子の表面的な (1) H横断リラクゼーション率を決定した.
- スキャラカップルプロトンを持つ分子におけるリラックス速度測定を可能にしました.
結論:
- 開発された方法は,エコーモジュレーションを効果的に消し,正確な (1) H横断リラクゼーション速度測定を可能にします.
- このテクニックは,NMRリラクゼーション研究の適用範囲を,複雑でスケーラ結合スピンシステムに拡大します.
- CsA.のようなバイオ分子の分子動力学と構造に関する貴重な洞察を提供します.
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