関連する実験動画
Updated: Jul 1, 2026

11:43
Hyperpolarized 13C Metabolic Magnetic Resonance Spectroscopy and Imaging
Published on: December 30, 2016
13C-13C回転共鳴幅距離測定は,均一に13Cとラベル付けされたペプチドで測定したものです
Ramesh Ramachandran1, Vladimir Ladizhansky, Vikram S Bajaj
1Francis Bitter Magnet Laboratory and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, USA.
Journal of the American Chemical Society
|December 11, 2003
まとめ
回転共鳴幅 (R2W) 実験は,生物学的固体内の距離を正確に測定します. この方法は,以前の技術の限界を克服し,均一にラベル付けされたシステムに対して,正確なサイト固有の測定を可能にします.
科学分野:
- 固体核磁気共鳴 (NMR) スペクトロスコーピーの固体核磁気共鳴 (NMR) スペクトロスコーピーは,固体核磁気共鳴 (NMR) スペクトロスコーピーの固体核磁気共鳴 (NMR) スペクトロスコーピーの固体核磁気共鳴 (NMR) の固体核磁気共鳴 (NMR) の固体核磁気共鳴 (NMR) の固体核磁気共鳴 (NMR) の固体核磁気共鳴 (NMR) の固体磁気共鳴 (NMR) の固体磁気共鳴 (NMR) の固体磁気共鳴 (NMR) の固体磁気共鳴 (NMR) の固体磁気共鳴 (NMR) の固体磁気共鳴 (NMR) の固体磁気共鳴 (NMR) の固体磁気共鳴 (NMR) の固体磁気共鳴 (NMR)
- 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
背景:
- 従来の回転共鳴 (R2) 実験では,時間の経過とともに磁化交換を測定します.
- 二極結合とリラックスパラメータの両方を同時に抽出することは困難です.
- 二極切断効果は,均一に標識された固体における距離測定を制限する.
研究 の 目的:
- 固体内の距離を測定するための回転共振幅 (R2W) 実験を導入し,検証する.
- 2D 13C-13C化学シフト相関スペクトロスコーピーと組み合わせたR2Wの有用性を実証するために.
- 二極断絶を克服することによって,均一にラベル付けされた生物系にR2Wの適用性を示すために.
主な方法:
- 常時回転共振幅 (R2W) 実験を利用した.
- サンプル回転周波数の関数として測定された磁化交換.
- 組み合わせたR2Wと二次元13C-13C化学シフト相関スペクトロスコーピー.
主要な成果:
- 双極結合と放松のパラメータを独立かつ明瞭に抽出しました.
- R2W実験における減弱された二極切断効果.
- N-アセチル-[U-13C,15N]l-Val-l-Leuで複数の13C-13C距離 (3-6 Å) を +/-0.5 Åの精度で正確に測定しました.
- 2回転モデルからの距離制約は,X線結晶学データと良好な一致を示しました.
結論:
- R2W実験は,構造およびリラックスパラメータの抽出に有利です.
- R2Wは,二極断絶を克服し,均一にラベル付けされた生物系に適用できます.
- このテクニックは,固体構造分析のための正確でサイト特有の距離測定を提供します.
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