ペプトイドにおける骨幹アミド結合のシス/トランスイソメリゼーションの運動学と均衡
Qiang Sui1, Dan Borchardt, Dallas L Rabenstein
1Department of Chemistry, University of California, Riverside, California 92521, USA.
Journal of the American Chemical Society
|September 11, 2007
まとめ
N置換のグリシンオリゴーマー (ペプトイド) は,骨幹アミド結合の有意なシス/トランスイソメリゼーションを示し,シス構成はプロリンを含むペプチドよりも多く存在します. このイソメリゼーションはペプトイドではペプチドよりも一般的に遅い.
科学分野:
- 超分子化学とは
- オーガニック化学 オーガニック化学
- 生物物理化学 生物物理化学とは
背景:
- N置換グリシンオリゴーマー (ペプチド) は,独特の構造特性を有するペプチド模倣物です.
- ペプトイドは,シスとトランスアミド結合の構成の両方の有意な集団を示し,コンフィギュレーションイソマーの複雑な混合物につながります.
研究 の 目的:
- N-アセチル化ペプトイド単体,ディペプトイド,およびトリペプトイドのシス/トランスイソメリゼーションの運動学と均衡を調査する.
- ペプトイドアミド結合のイソメリゼーションダイナミクスをプロリンを含むペプチドのイソメリゼーションダイナミクスを比較する.
主な方法:
- 核磁気共振 (NMR) スペクトロスコピーはペプトイドサンプルを研究するために使用されました.
- 逆転磁気化移転技術は,温度範囲における速度定数を測定するために使用されました.
- シス/トランスイソメリゼーションの活性化パラメータは,温度に依存する速度定数から導かれました.
主要な成果:
- 共鳴強度は,アサイクロンペプチドの類似結合と比較して,ペプトイド骨幹のアミド結合におけるシス構成のより高い集団を示した.
- ペプトイドアミド結合の周囲のシス/トランスイソメリゼーションの速度は,プロリン残基に対するアミド結合の周囲の速さよりも一般的に遅かった.
- NMRの逆転磁気化移転時間スケールのイソメリゼーションは,C端ペプトイド残基に対するアミド結合の周りの回転のみで観察されました.
結論:
- ペプトイド骨幹アミド結合は,従来のペプチドと比較して異なったシス/トランスイソメリゼーション行動を示す.
- ペプトイドの形状の柔軟性とイソメリゼーションのダイナミクスは,その生物学的活動と構造的特性に影響を及ぼします.
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