ヘテロ核のスピンロック緩和率を正確に測定するためのNMR実験
Dmitry M Korzhnev1, Nikolai R Skrynnikov, Oscar Millet
1Protein Engineering Network Centers of Excellence and Departments of Medical Genetics, Biochemistry and Chemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.
Journal of the American Chemical Society
|September 5, 2002
まとめ
研究者らは,一般的な核磁気共鳴 (NMR) 技術は,タンパク質ダイナミクス測定を過大評価することができると発見しました. 特定の (1) H解離法により,異核回転枠のリラクゼーション速度 (R(1) ((rho)) の測定に誤差が生じる.
科学分野:
- 核磁共振 (NMR) スペクトロスコーピーは,核磁共振 (NMR) スペクトロスコーピーを用いて行われます.
- タンパク質のダイナミクス
- 生物物理化学 生物物理化学
背景:
- ローテーションフレームのリラクゼーション率 (R(1) ((rho)) は,NMRを用いたタンパク質動態の研究に不可欠です.
- 既存のNMR方法は,二極二極と化学シフトアニソトロピー (CSA) のリラックスメカニズム間のクロス相関を抑制することを目的としています.
研究 の 目的:
- ヘテロ核Rho測定におけるシステマティックなエラーを特定し,修正する.
- 緩解率の精度に対する特定の解離スキームの影響を調査する.
主な方法:
- (15) N - 1) H と (13) C - 1) H のスピンシステムにおけるRho測定の実験的検証.
- 共通のNMRパルスシーケンスの下でのリラックスメカニズムの理論的分析.
- アーティファクトを排除するスキームの開発とテスト.
主要な成果:
- 標準の (1) H WALTZ16の解離と正規のパルス間隔は,異核のR ((1) ((rho) 値の過大評価につながります.
- これらの誤差は,交差相関効果の抑制から生じます.
- (15) N-(1) Hと (13) C-(1) Hのリラクゼーション測定の両方で,人工物が見つかりました.
結論:
- 交差相関を抑制するための現在のNMR方法論は,R ((1) ((rho)) 測定に実質的なエラーを導入することができます.
- これらのアーティファクトを修正するためのシンプルで効果的なスキームが提案されています.
- 精密なタンパク質ダイナミクスパラメータは,スピンロックリラックスデータ分析のためのこれらの改良された方法論の採用を必要とします.
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