ビエンジム触媒および酸化媒介によるアントラキノン環開封
Feifei Qi1,2,3, Wei Zhang1,2,3,4, Yingying Xue5
1Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, China.
Journal of the American Chemical Society
|September 29, 2021
まとめ
菌類のセコアントラキノン生物合成には,アントラキノン環の開きが含まれています. 研究者は2つの酵素メカニズムであるGedFとGedKを特定し, 還元と酸化によるこの重要なステップを担当しています.
科学分野:
- 生物化学
- 分子生物学
- 菌類学
背景:
- アントラキノン環の分裂は,キノコのセコアントラキノン生物合成に不可欠です.
- 正確なメカニズム,特にC-10-C-4a結合分裂は不明であり,以前はBaeyer-Villiger酸化が提案されていた.
- このリング開く過程に関する遺伝的,酵素的,化学的なデータは欠けていた.
研究 の 目的:
- クエストイン生物合成におけるアントラキノン環開閉の修正されたメカニズムを解明する.
- C-10-C-4a結合分裂に関与する特定の酵素とコファクターを特定する.
- 提案されたリング開通経路の普遍性を示します.
主な方法:
- 重要な遺伝子を特定するための"イン・ビボ"遺伝子破壊研究
- 酵素機能を特徴づけるための"インビトロ"酵素測定法
- 反応中の酸素の取り込みを追跡する実験を行いました
主要な成果:
- NADPHを用いたGedF還元酵素は,クエストインのC-10ケト群をヒドロキシル群に還元することが確認された.
- 非典型のコファクターフリーなダイオキシゲナーゼGedKは,結果として発生するクエストリンヒドロキノンのC-10-C-4a結合を分裂させる酵素として特定された.
- この酵素作用により デスメチルスロクリンが生成され,新しいリング開きメカニズムが明らかになった.
結論:
- アントラキノン環の開くための修正されたバイ酵素触媒メカニズムが解明されました.
- この経路は,GedFによる連続的還元と,GedKによるコファクターフリー酸化を含みます.
- このメカニズムは,キノコのセコアントラキノン生物合成における普遍的な経路であると提案されています.
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