コンピュータ設計による人工金属酵素の触媒性能の改善
Tillmann Heinisch1, Michela Pellizzoni1, Marc Dürrenberger1
1†Department of Chemistry, University of Basel, 4056 Basel, Switzerland.
Journal of the American Chemical Society
|July 31, 2015
まとめ
計算上の設計により,非対称的還元における触媒活性とエナチオ選択性を改善するために,人工移転水酸化酵素 (ATHases) を最適化した. この改良された酵素設計により,重要な医薬品前駆体である (S) - サルソリジンの生産量が増加しました.
科学分野:
- 生物触媒
- コンピュータ化学
- 酵素工学
背景:
- 人工金属酵素は,小分子触媒の反応性と酵素の選択性を結合する.
- 触媒の特性を調整するには,特定の用途のための新しい方法が必要です.
- 構造ベースのコンピューティングデザインは 改良された酵素変種を設計するための経路を提供します
研究 の 目的:
- ロゼッタ・デザインを用いて人工的移転ヒドロゲンゼ (ATHase) を遺伝子的に最適化する.
- アシンメトリックなイミン減少のための触媒活性とエナチオ選択性を強化する.
- タンパク質の変異と触媒の改変がATHaseの性能に与える影響を調査する.
主な方法:
- 結晶構造に基づくタンパク質工学のロゼッタ設計の応用
- 安定性や水害性のあるhCAII変異の発生
- 触媒とタンパク質の親和性を決定するダンシラミド対抗試験
- サルソリジンのサイクルイミン前駆体に対する非対称的還元.
- イリジウム触媒のCp*-moetyの修正により,水嫌性が増加する.
主要な成果:
- 4つのhCAII変種は,イリジウム複合体に対する46~64倍以上の親和性を示した.
- (S) サルソリジンの生成に対するエナンチオ選択性は70%から92%まで増加した.
- 総売上高が4倍になった.
- プロピル置換剤を用いた改良された触媒は,このATHaseの最高選択性を96%ee達成した.
- X線結晶検査で タンパク質の構造にコファクターが埋め込まれていることが確認されました
結論:
- 構造ベースのコンピューティングデザインは ATHase のパフォーマンスを成功裏に最適化しました.
- エンジニアリングされたATHasesは,著しく強化された活性とエナチオ選択性を示しています.
- タンパク質工学と組み合わせた触媒の改変は,ステレオ選択性をさらに改善します.
- この研究は,高度に選択的な人工金属酵素を設計するための検証された計算方法を提供します.
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