化合物Iは,シトクロームP450の同位体間で有意に異なっているか?
Richard Lonsdale1, Julianna Oláh, Adrian J Mulholland
1Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, United Kingdom.
Journal of the American Chemical Society
|August 26, 2011
まとめ
サイトクロームP450 (CYP) 化合物Iの電子構造の差異は,ヒトイソフォームの活性変化を説明する可能性は低い. 基板の存在は,CYPイソフォームの間でコンパウンドIの安定性をわずかに低下させる.
科学分野:
- バイオケミストリー バイオケミストリー
- コンピューティング・ケミストリー
- 酵素学 酵素学とは
背景:
- サイトクロームP450 (CYP) 酵素は,薬物開発において極めて重要です.
- CYPイソフォームの反応性の差異は,化合物Iの電子構造の変動から生じるという仮説があります.
- 現在のモデルは,多くの場合,すべてのCYPイソフォームに共通する単一の化合物Iを想定しています.
研究 の 目的:
- CYP化合物Iの電子構造とFe-O結合エンタルピーの計算方法を開発する.
- 人間および細菌のCYPイソフォームにおける化合物Iの電子構造を調査する.
- 化合物Iの電子構造がCYPイソフォームの活性における役割を評価する.
主な方法:
- 形状の柔軟性を捉えるために分子動力学シミュレーションを使用します.
- 構造最適化のためのQM/MMと密度関数理論 (B3LYP) を利用する.
- 電子構造を計算し,化合物IのFe-O結合エンタルピーを推定する.
主要な成果:
- ヒトCYPイソフォームの化合物Iの電子構造の差異は最小限である.
- ヒトの単一の同型体内の多様性は,同型体間の違いよりも大きかった.
- ヒトのCYPとP450の間で注目すべき電子構造の違いが発見され,これは水素結合環境に関連している.
- 基質の存在は化合物I Fe-O結合エンタルピーが低下し,安定性が低下していることを示しています.
結論:
- 化合物Iの電子構造の差異は,ヒトのCYPイソフォームの活性変化の主な要因である可能性は低い.
- P450の独特の電子構造は,特定のアクティブサイト環境に関連している可能性があります.
- 化合物Iは,潜在的に水位移転による,基板の存在で安定性が低下しているように見えます.
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