ダイナミックな核極化によって強化された (15) N-コリン代謝物の陽子NMR
Riddhiman Sarkar1, Arnaud Comment, Paul R Vasos
1Laboratory for Biomolecular Magnetic Resonance, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland.
Journal of the American Chemical Society
|October 24, 2009
まとめ
動的核極化 (DNP) は窒素-15コリンをハイパーポラライズし,コリンからフォスフォコレンの変換のような代謝変換の強化された陽子NMR研究を in vitro および in vivo で可能にします.
科学分野:
- バイオケミストリー バイオケミストリー
- 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
- メタボロミクスとは
背景:
- 陽子の化学的シフトは,コリンからフォスフォコリンへの変換を含む代謝経路の洞察を提供します.
- ダイナミック・ニュクレア・ポラライゼーション (DNP) は,NMR研究における感度向上のために核スピン磁化を強化する技術です.
- In vivoの代謝追跡には,敏感で効率的なNMR方法が必要です.
研究 の 目的:
- DNPを使用した窒素-15ラベルコリンをハイパーポラライズする方法を開発する.
- この強化ポラライゼーションを窒素-15から陽子に移し,DNP強化型陽子NMRを行う.
- コリン代謝のインビトロおよびインビボの研究を可能にするために.
主な方法:
- 窒素-15のハイパーポラライゼーションは,DNPを1.2Kと3.35Tで使って,15Nラベル付けのコレインに回転する.
- 超極化のために94GHzでTEMPOラジカルの電子スピン共振を照射する.
- 強化ポラライゼーションを窒素15からスキャラカップリングを通じてメチルとメチレン陽子に転送する.
- 部分デュテレーションによる窒素極化寿命 (T(1) の最適化.
主要な成果:
- コリン中の窒素-15スピンの高極化3.3%まで達成.
- 強化ポラライゼーションを陽子に成功裏に転送しました.
- 室温窒素の極化寿命が約200sで,デュテレーションにより延長することが示されました.
- コリン代謝産物のDNP強化型陽子NMRの実行可能な方法を確立しました.
結論:
- 窒素-15コリンのDNPハイパーポラライゼーションは実現可能で効果的です.
- このテクニックは,コリン代謝産物に対する陽子NMR感受性を大幅に高めます.
- 開発された方法は,in vitroおよびin vivoの代謝研究において有望である.
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