チャエトグローボシンA生物合成におけるリドックス酵素による複合性の組み合わせ生成
Kan'ichiro Ishiuchi1, Takehito Nakazawa, Fumitoshi Yagishita
1Department of Pharmaceutical Sciences, University of Shizuoka, Shizuoka 422-8526, Japan.
Journal of the American Chemical Society
|April 25, 2013
まとめ
この研究は,チャエトグローボシンAの完全な生物合成を詳細に説明し,主要な酸化還元酵素と中間物質を特定しています. Chaetomium globosumのこれらの経路を理解することは,天然製品の発見に役立ちます.
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
- 酵素学 酵素学とは
背景:
- レドックス酵素は,天然製品の構造的複雑性を生み出す上で極めて重要です.
- チャエトグロボシンAは複合的な天然製品で,ハイブリッド経路で生物合成されます.
- チャエトグローボシンのファミリーには,異なる酸化状態を持つ同類物が含まれる.
研究 の 目的:
- チョエトログロボシンAからチョエトログロボシンIの完全な生物合成経路を解明する.
- それぞれの酸化ステップに責任を負う特定のリドックス酵素を特定するために.
- チャエトグローボシンA生物合成のステレオ化学的経路と中間物質を決定する.
主な方法:
- リドックス酵素遺伝子 (FAD依存モノオキシゲナーゼ,サイトクロームP450s) の欠損があるChaetomium globosum菌株を使用した.
- Saccharomyces cerevisiaeの遺伝子の異質発現による in vivo 生物変換実験を行った.
- X線結晶構造解析を用いて,特定された5つの中間物質の絶対的構成を決定した.
主要な成果:
- 5つの新しいアナログがproxvetoglobosin IをChaetoglobosin Aに酸化する中介物質として特定されました.
- 酸化ステップの完全なシーケンスとそれらを触媒する酵素を解明しました.
- レドックス酵素の乱交性を明らかにし,経路のネットワークと中間物質の組合せ的形成につながった.
結論:
- この研究では,チャエトグロボシンAの完全な生物合成経路のマッピングに成功しました.
- 特定の酸化還元酵素の重要な役割と,構造的多様性を生み出す上でそれらの乱交性を実証した.
- 提示されたアプローチは,他の真菌天然製品の生合成経路の解明を加速することができます.
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