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Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
負イオン電子捕獲解離:電荷が増加したガス状ペプチドアニオンの根性駆動による断片化
Hyun Ju Yoo1, Ning Wang, Shuyi Zhuang
1Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055, USA.
Journal of the American Chemical Society
|September 28, 2011
まとめ
研究者らは,新しい質量スペクトロメトリ技術である負イオン電子捕獲解離 (niECD) を開発した. この方法により,酸性ペプチドやタンパク質の分析が可能で,既存の方法には難しい課題となっている.
科学分野:
- アナリティカル・ケミストリー (Analytical Chemistry) とは
- バイオケミストリー バイオケミストリー
- マススペクトロメトリーによる質量スペクトロメトリーです.
背景:
- コロンブ・バリアを持つガス型ポリアニオンは興味深いものですが,生物学的アニオンは報告されていません.
- ペプチドとタンパク質カチオンへの電子結合は,タンデム質量スペクトロメトリ (MS/MS) に有用である.
- 電子捕獲解離 (ECD) や電子移転解離 (ETD) などの既存の方法は,陽子には有効だが,酸性アニオンには理想的ではない.
研究 の 目的:
- ペプチドアニオンによる電子捕獲を調査するために.
- 酸性ペプチドとタンパク質を分析するための新しいMS/MS技術を開発する.
- 負イオンモードでの電子捕獲後の解離のメカニズムを探求する.
主な方法:
- 特定のエネルギー範囲 (3.5-6.5 eV) 内のペプチドアニオン ([M - nH](n-)) に電子が結合する.
- 電子を捕獲した後に形成された,電荷を増やした基質中間物質の分析.
- ECD/ETDに類似する解離パターンの調査.
主要な成果:
- ペプチドアニオンは電子を捕獲し,分裂する中間基を形成します.
- 解離はECD/ETDに類似しており,予測可能な産物イオンを生成します.
- ガス相ズウィテリオン構造は,新しいネガイオン電子捕獲解離 (niECD) プロセスに関与しています.
結論:
- 負イオン電子捕獲解離 (niECD) は,実行可能なMS/MS技術である.
- niECDは,翻訳後の改変を含む酸性ペプチドやタンパク質を分析するのに特に有用です.
- この方法は,生物サンプルにおける質量スペクトロメトリーにおける電子ベースの解離の適用性を拡大します.
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