鉄酸化酵素によって-2-オキシグルタレートからエチレンを分離するためのハイブリッド・ラジカル・ポラー経路
Rachelle A Copeland1, Shengbin Zhou1, Irene Schaperdoth1
1Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA.
Science (New York, N.Y.)
|August 13, 2021
まとめ
微生物のエチレン形成酵素 (EFE) は,2-オキシグルタレット (2OG) からエチレンを独特の根極性ハイブリッドメカニズムで生成する. この発見は2OG依存酵素の新たな酵素能力と潜在的応用を明らかにした.
科学分野:
- 生物化学
- 酵素学
- 有機化学
背景:
- 微生物のエチレン形成酵素 (EFE) は,2- オキシグルタレート (2OG) のエチレンへの変換を触媒化する.
- EFEのメカニズムは,関連する酵素とは異なり,議論の対象となっている.
研究 の 目的:
- 微生物のエチレン形成酵素 (EFE) の反応機構を解明する.
- 2OGからエチレン形成中のステレオ化学的結果と酸素の組み込みを調査する.
主な方法:
- ステレオ化学的に定義された [2H2]-2OGを用いた同位体ラベリング試験
- エチレンステレオ化学の分析 (cis/trans比)
- 炭酸塩の形成と製品の多様化のための酸素源の調査
主要な成果:
- EFEは,3S,4R) - [2H2]-2OGからステレオ化学的にランダムな (cisとtrans) 1,2-[2H2]-エチレンを生成する.
- O2からの酸素はC1由来 (二酸化炭素) 製品に組み込まれます.
- 酵素と基質の改変により, ω-ヒドロキシル化モノ酸産物が生じる.
結論:
- この結果は,鉄を含む異常な根極性ハイブリッドメカニズムを裏付けている (II).
- このメカニズムは,高エネルギーカルボキシル基にアクセスするアシルペロキシカルボネートとアルキルカルボネート中間物質を含む.
- この発見は,2OG依存酵素の未発見の能力を示唆し,利用の可能性も示しています.
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