調節可能な赤外線マルチフォトン解離で探査された電荷タグペプチドからの電子捕獲解離断片の構造

Gilles Frison¹, Guillaume van der Rest, Frantisek Turecek

¹Laboratoire des Mécanismes Réactionnels, Department of Chemistry, Ecole Polytechnique and CNRS, 91128 Palaiseau, France.

Journal of the American Chemical Society

|October 22, 2008

まとめ

電子捕捉解離 (ECD) は,エノル-イミンの構造ではなく,アミド構造のペプチドc型イオンを形成する. この発見は,赤外線スペクトロスコピーを用いたECDメカニズムを明確にします.

科学分野:

質量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.
化学物理化学物理
構造生物学構造生物学とは

背景:

電子捕獲解離 (ECD) により生成されるペプチドc型イオンの構造的特徴は,依然として議論の対象となっている.
提案された構造には,イノールイミンとアミドの形態が含まれるが,これらは同位体であり,質量スペクトロメトリだけで区別できない.

研究の目的:

ECDによって生成されるc型イオンの構造をスペクトル顕微鏡で決定する.
ECDにおけるc型イオン形成のメカニズムを解明する.

主な方法:

調節可能な自由電子レーザーとフーリエ変換イオンサイクロトロン共振 (FT-ICR) 質量スペクトロメーターの結合.
赤外線 (IR) スペクトロスコピーは,同位体イオン構造を区別する.

主要な成果:

spetroscopic 証拠は,c型イオンがアミド構造 (-C(O) -NH2) を持っていることを確認します.
1731cm ((-1)) で,C=Oの伸びの特徴的なIRシグネチャーが観察されました.

結論:

この研究は,ECDによって形成されるc型イオンのアミド構造を決定的に確立した.
この構造的決定は,電子捕獲解離の基本的メカニズムに関する重要な洞察を提供します.

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