シトクロームP450カム (CYP101A1) の基質依存性アロステリック調節
Alec H Follmer1, Mavish Mahomed2, David B Goodin2
1Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry , University of California , Irvine , California 92697-3900 , United States.
Journal of the American Chemical Society
|October 31, 2018
まとめ
サイトクロームP450カムには第二の基板部位があります. このアロステリック部位に第2の基板分子が結合すると,基板の入り口と製品の出口が開き,協力性が明らかになる.
科学分野:
- 生物化学
- 分子生物学
- 酵素学
背景:
- サイトクロームP450カムはよく研究された酵素です.
- 証拠は第二の基板結合部位を示唆しているが,その役割は不明である.
- 活性サイトチャネルを通じた基板/製品の輸送を理解することは極めて重要です.
研究 の 目的:
- サイトクロームP450camにおける第2基板結合部位の位置と生物学的関連性を調査する.
- サブストラット結合と製品の出血のメカニズムを解明する.
- 異なるバインディングサイト間の協力の可能性を探求する.
主な方法:
- 分子ダイナミクスのシミュレーションが採用された.
- 基板と製品の結合と排出経路の分析
- チャネルダイナミクスとアロステリックサイト相互作用の調査
主要な成果:
- 遠隔アロステリック部位が特定され,基板結合と産物排出に影響を与えました.
- 2番目の基板分子がアロステル部位に結合すると,チャンネル1が開きます.
- 新しい出口チャネル (チャネル2) が,基板の入口と製品の出口を容易にします.
- 活性部位とアロステル部位との協力性が示された.
結論:
- この研究は,アロステリック部位とP450camの活性部位とのダイナミックな相互作用を明らかにした.
- この相互作用は,基質へのアクセスと製品放出を調節することによって,酵素の活性を制御します.
- この発見は,P450camの機能に関する以前の実験観察と一致しています.
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