H2Oにおけるアミド-アミドおよびアミド-炭化水素相互作用の実験的原子別解剖
Xian Cheng1, Irina A Shkel1, Kevin O'Connor1
1Program in Biophysics and ‡Departments of Biochemistry and §Chemistry University of Wisconsin-Madison , Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|July 6, 2017
まとめ
この研究は,水中のアミドの相互作用を,オスモメトリーと溶解性を用いて定量化します. タンパク質の折りたたみと水性過程の理解に不可欠なアミド,尿素,炭水化物の間の好ましいと不利な相互作用を明らかにしています.
科学分野:
- 生物物理化学
- 化学物理学
- 分子 相互作用
背景:
- 水中のアミド相互作用の定量的な理解は,タンパク質の折りたたみと水性プロセスにとって不可欠である.
- 計算シミュレーションと比較するには,これらの相互作用に関する正確な実験データが必要です.
研究 の 目的:
- 水中のアミドの相互作用を定量化するために,様々な原子中心を持つ尿素とアルキル化された尿素を含みます.
- 水溶液中のアミド-芳香炭化水素の相互作用を決定する.
- 生物学的および化学的システムにおけるアミドおよび炭化水素効果の予測と解釈のための基礎を提供すること.
主な方法:
- 水中の尿素とアルキル尿素の相互作用を測定するためにオスモメトリーを使用した.
- アミド-アロマティック炭化水素の相互作用を定量化するために溶解度測定を用いた.
- 水中の特定の原子中心 (sp2O,sp2N,sp3C,sp2C) との相互作用強度を分析した.
主要な成果:
- アミドsp2Oと尿素とナフタレンとの相互作用は好ましいが,アルキル尿素と不良であり,アルキル化により悪化する.
- sp2O- sp2N (水素結合) とsp2O- 芳香性sp2C (π-π*) との好ましい相互作用が観察された.
- 不利なアミドsp2O- sp3C相互作用は,アルキル化によって増加する好ましい尿素- sp3Cおよび尿素- アミドsp2N相互作用と対照的です.
結論:
- この研究は,水中のアミド,尿素,炭化水素の定量的な相互作用強度を提供します.
- これらの発見は,バイオポリマーと水性プロセスにおけるアミドと炭化水素分子の相互作用の予測と解釈を可能にします.
- 結果はシミュレーションと比較し,タンパク質の折りたたみで埋もれた表面積の決定を容易にする.
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