衝突活性化時に,アミド水素のプロトン化ペプチドへの分子内移動
Thomas J D Jørgensen1, Henrik Gårdsvoll, Michael Ploug
1Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense M, Denmark. tjdj@bmb.sdu.dk
Journal of the American Chemical Society
|February 24, 2005
まとめ
ガス状のプロトン化ペプチドは,衝突活性化時に,完全なアミド水素混ざりを受けます. この発見は,デュテリウムラベリング実験のタンデム質量スペクトロメトリーデータを解釈する上で極めて重要です.
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:
- 衝突活性化時に陽子化ペプチドにおけるアミド水素乱射の程度は議論されている.
- デウテリウム交換実験からの正確なサイト固有の情報は,最小限のスクランブルに依存しています.
研究 の 目的:
- 低エネルギー衝突活性化中にペプチド内の分子内アミド水素移動を調査する.
- ガス状ペプチドイオンにおける水素乱射の程度を決定する.
主な方法:
- 異なる結合領域と非結合領域を持つ,地域選択的にデウテリウムラベル付ペプチドを使用した.
- 長寿受容体複合体を介してラベルペプチドを生成し,ペプシンタンパク質分解を介してラベル領域選択性を確認しました.
- Q-TOF ESI質量スペクトロメトリを用いた衝突誘発解離 (CID) の断片イオン (b-およびy-イオン) を分析した.
主要な成果:
- 断片イオンのデュテリウム含有量は,100%スクランブル化の理論値とほぼ一致しました.
- 窒素と酸素に結合した水素原子の完全なランダム化が観察されました.
結論:
- ガス状の陽子ペプチドの衝突誘発解離 (CID) は,アミド水素の完全な乱れにつながります.
- この完全なスクランブルは,サイト特有の水素/デュテリウム交換研究のためのタンデム質量スペクトロメトリデータを解釈する際に考慮する必要があります.
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