単体および多重電荷ペプチドの電子イオン化解離

Y M Eva Fung¹, Christopher M Adams, Roman A Zubarev

¹Division of Molecular Biometry, Department of Medicinal Biochemistry and Biophysics, Karolinska Institutet, SE-17 177 Stockholm, Sweden.

Journal of the American Chemical Society

|July 23, 2009

まとめ

電子離子解離 (EID) は,100%を超える高効率でイオンを断片する新しい質量スペクトロメトリ技術です. この方法は,ボトムアップとトップダウンの両方のプロテオミクス分析に有効です.

科学分野:

アナリティカル・ケミストリー (Analytical Chemistry) とは
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.
プロテオミクスプロテオミクスは,プロテオミクスの

背景:

タンデム質量スペクトロメトリは,タンパク質の識別と特徴づけに不可欠です.
既存の断片化技術には,効率と断片化パターンの限界があります.

研究の目的:

新しいタンデム質量スペクトロメトリ技術である電子イオン化解離 (EID) を導入し,特徴づけること.
プロテオミクスのアプリケーションにおけるEIDの効率と断片化能力を評価する.

主な方法:

捕まったカチオン [M + nH] (n+) を高速電子 (エネルギー > 離子化値) で照射する.
同時にイオン化と電子刺激を誘導し,断片化につながります.
サイドチェーンの損失と脊髄分裂 (N-C ((alpha) とC-C結合) を含む断片イオンの分析.

主要な成果:

EIDは,理論的な断片化効率が100%を超えることを可能とする.
EIDは,c-/z型 (N-C ((alpha) 割れ目) とa-/x型 (C-C 割れ目) の断片の両方を生成します.
この技術は,電気スプレーイオン化 (ESI) やマトリックスアシストレーザー脱吸収/イオン化 (MALDI) によって生成されるイオンに適用できます.

結論:

EIDは,質量スペクトロメトリのための非常に効率的な断片化方法を提供します.
このテクニックの汎用性により,ボトムアップとトップダウンの両方のプロテオミクスに適しています.
重要なエネルギーを吸収するEIDの能力は,複雑なタンパク質構造を分析するのに有望です.

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