エポキシドヒドロラゼ-ラサロシドの構造は,ポリエーテル天然製品バイオシンセシスのメカニズム的な洞察を提供します
Fong T Wong1, Kinya Hotta, Xi Chen
1Department of Biological Sciences, National University of Singapore , 117543 Singapore.
Journal of the American Chemical Society
|December 24, 2014
まとめ
研究者らは,ポリエーテル天然製品バイオシンセシスにおける反バルドウィンサイクル化メカニズムを解明した. エポキシドヒドロラーゼLsd19の結晶構造は,ラサロシドAの生産中にこの運動的に不利な反応をどのように触媒化するかを明らかにします.
科学分野:
- バイオケミストリー バイオケミストリー
- 自然製品のバイオシンセシス
- 構造生物学 構造生物学とは
背景:
- ポリエーテル天然製品は,多様な生物学的活動を持つ複雑な分子です.
- バイオシンセシスはしばしば,運動的に不利なサイクライゼーションなど,困難な化学変換を含みます.
- 反バルドウィンサイクル化は,いくつかのポリエーテル天然製品におけるサイクルエーテル形成の重要なステップです.
研究 の 目的:
- ラサロシドA生物合成における反バルドウィン循環の構造的基礎とメカニズムを解明する.
- この過程におけるエポキシドヒドロラーゼLsd19の役割を特徴付ける.
- 関連する酵素によるエポキシド選択のための一般的なメカニズムを提案する.
主な方法:
- ラサロシドA.との複合体におけるLsd19の構造を決定するためのX線結晶学.
- 酵素活性 (暗示) を研究するための生化学的測定法.
- 反応機構を推論するための構造分析.
主要な成果:
- ラサロシドAと複合したLsd19の結晶構造が決定されました.
- Lsd19のC末端ドメインは,反バルドウィンサイクルに起因する触媒ドメインとして特定されました.
- この構造は,Lsd19がエポキシド基板をどのように選択し,処理するかを洞察します.
結論:
- Lsd19は,ラサロシドA生物合成の重要なステップである反バルドウィンサイクルを触媒化する.
- 酵素の構造は,この運動的に不利な反応のメカニズムを明らかにします.
- これらの発見に基づいて,イオノフォアポリエーテルエポキシド水酸化物によるエポキシド選択の一般的なモデルを提案することができます.
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