ダイエレクトリック環境の同位体への影響 グライコシドの異解: 計算による評価と原子ヘッセン解析
Katarzyna Świderek1,2, Alexander J Porter2, Catherine M Upfold2
1Departament de Química Física i Analítica , Universitat Jaume I , 12071 Castellón , Spain.
Journal of the American Chemical Society
|December 31, 2019
まとめ
同位体効果は溶媒の極性に対して敏感であり,暗黙的および明示的な溶解モデルが洞察を提供している. Hessian マトリックスの小さなブロックは,溶媒を捕捉します.
科学分野:
- コンピュータ化学
- 物理化学
- 化学物理学
背景:
- 同位体効果は,周囲の媒体の極性によって影響を受けます.
- 暗黙の溶媒モデルは,均衡同位体効果 (EIEs) を予測できるが,矛盾を示す可能性がある.
- 酵素反応をモデル化するには,タンパク質環境を明確に考慮する必要があります.
研究 の 目的:
- 計算方法を使用して溶媒の極性に対するEIEの感受性を調査する.
- EIEを予測するための暗黙的および明示的な溶解モデルを比較する.
- 原子ヘッセン解析を用いて,溶媒のEIEへの貢献を分析する.
主な方法:
- 分子形の空洞を用いた暗黙の溶媒計算 (PCM法)
- コンフィギュレーション (QM/MM) を平均する明示的なソルベーション計算.
- B3LYP/6-31+G ((d)) と OPLS-AA フォースフィールドが使用されました.
- EIEへの主要な貢献を特定するための原子ヘッセン分析.
主要な成果:
- ヘテロリシスのEIEsは,210の範囲の相対性許容性に非常に敏感です.
- 異なるPCMの実装では矛盾する傾向が生じることがあります.
- 原子ヘッシアン分析は,3x3ブロックが暗黙的および明示的な溶解の両方でEIEに対する溶媒の影響を捉えていることを明らかにします.
- 明確な溶解は,カチオン移転の暗黙のモデルからの予測を確認した.
結論:
- 溶媒の極性は同位体効果に大きく影響する.
- 計算モデルを慎重に実装し解釈することは極めて重要です.
- 簡略化されたヘッセンブロックは,EIEsの溶媒効果を効果的に表します.
- QM/MMシミュレーションは溶液と酵素反応における同位体効果の解釈に役立つ.
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