関連する実験動画
Updated: Jul 13, 2026

11:43
Hyperpolarized 13C Metabolic Magnetic Resonance Spectroscopy and Imaging
Published on: December 30, 2016
3D TEDOR NMR実験は,均一に (13) C,(15) Nとラベル付けされた固体の中で,複数の炭素-窒素距離を同時に測定するためのものです
Christopher P Jaroniec1, Claudiu Filip, Robert G Griffin
1Department of Chemistry, Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Journal of the American Chemical Society
|September 5, 2002
まとめ
新しい3次元マジック・アングル・スピニング・NMR実験により,固体における複数の炭素-窒素距離の正確な測定が可能になりました. これらの高度なテクニックは,Jカップリングによる課題を克服し,生物分子に対する重要な構造的洞察を提供します.
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.
- 生物物理化学 生物物理化学
- 構造生物学 構造生物学とは
背景:
- マジック・アングル・スピニング (MAS) NMRは,固体材料の研究に不可欠です.
- 固体における核間距離の測定は,構造的決定において極めて重要です.
- 以前の3D転送エコーダブル共鳴 (TEDOR) 技術は,同核のJ結合により制限に直面していました.
研究 の 目的:
- 均一に標識された固体における複数の炭素-窒素 (C-N) 距離を同時に測定するための新しい3D MAS NMR実験を開発する.
- C-N距離測定における同核炭素-炭素 (C-C) Jカップリングの有害な影響を克服するために.
- 固体サンプルにおける構造的制約のより正確かつ信頼性の高い決定を可能にする.
主な方法:
- C-Nコヒーレンス転送のために,移転エコーダブル共鳴 (TEDOR) による3次元マジック・アングル・スピニングNMR実験を活用しました.
- 場所固有の解像度のための採用された (15) N および (13) C 周波数ラベリング.
- ホモ核 (13) C-(13) C J-カップリングの有害な影響を回避するためのパルス配列を開発し,zフィルター周期と帯域選択 (13) Cパルスを含む.
- 複数のスピン・スピン結合を考慮して,クロスピークの蓄積から核間距離を抽出するために単純な分析モデルを適用しました.
主要な成果:
- 均一に (13) C,(15) N-ラベル付けペプチド (N-ac-VLとN-f-MLF) で複数のC-N距離を測定しました.
- N-ac-VLでは20のC-N距離,N-f-MLFでは26の距離まで~6 Åまで定量化されています.
- N-ac-VLで10の距離>3 Å,N-f-MLFで13の距離>3 Åを特定し,貴重な構造的制約を提供しました.
結論:
- 新しい3DTEDOR NMR実験は,有害なJ結合効果を効果的に抑制し,固体における正確なC−N距離測定を可能にします.
- これらの方法は,ペプチドおよび潜在的に他の固体生物分子に対する信頼性の高い構造的制約を提供します.
- 開発された技術は,詳細な分子構造の解明のために,固体NMRの能力を向上させます.
関連する概念動画
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¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
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Two-Dimensional (2D) NMR: Overview
The 1D NMR spectrum of large and complex molecules like natural products has complicated splitting patterns and overlapping signals, which can be easily interpreted using 2-dimensional (2D) NMR. Unlike 1D NMR, 2D NMR has two frequency axes that provide the coupling information between the nucleus A and nucleus B in a molecule. The process from which 2D spectra are obtained has four steps.
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¹³C NMR: ¹H–¹³C Decoupling
The probability of having two carbon-13 atoms next to each other is negligible because of the low natural abundance of carbon-13. Consequently, peak splitting due to carbon-carbon spin-spin coupling is not observed in spectra. However, protons up to three sigma bonds away split the carbon signal according to the n+1 rule, resulting in complicated spectra.
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
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Double Resonance Techniques: Overview
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
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2D NMR: Overview of Homonuclear Correlation Techniques
Homonuclear correlation spectroscopy (COSY) is a powerful technique used in Nuclear Magnetic Resonance (NMR) spectroscopy to study the correlations between nuclei of the same type within a molecule. It provides information about scalar couplings between adjacent nuclei, which helps determine connectivity and structural information. There are several COSY variants, each with its unique strengths and experimental parameters.
COSY90 is the standard two-dimensional (2D) COSY experiment that...
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