クラスIIのピルバートアルドラーゼBphIのステレオ選択性の合理的設計
Perrin Baker1, Stephen Y K Seah
1Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1.
Journal of the American Chemical Society
|November 16, 2011
まとめ
研究者は,クラスIIのピルバ酸アルドラーゼ酵素を設計して,ステレオ補完的なバージョンを作成しました. これらの新しい酵素は,有機合成のためのキラル4-ヒドロキシ-2-オクソ酸の構成要素を生成します.
科学分野:
- 酵素学 酵素学とは
- 有機化学 オーガニック・ケミストリー
- バイオカタリシス バイオカタリシス
背景:
- クラスIIのピルバートアルドラーゼは,可逆性炭素-炭素結合形成を触媒化する.
- BphI酵素は (S) 構成の4-ヒドロキシ-2-オキシ酸を作り出します.
- アクティブサイト残留物Leu-87は,基板特異性にとって極めて重要です.
研究 の 目的:
- ステレオコンプリメンタリークラスIIのピルバートアルドラーゼを設計する.
- (R) 構成の4-ヒドロキシ-2-オクソ酸を生成する酵素を作成する.
- キラルシントン生成のためのバイオカタリティクツールを拡張する.
主な方法:
- Leu-87とTyr-290でのBphIのサイト指向型変異.
- アルドール添加とデカルボキシル化のための酵素活性測定法.
- 製品のステレオ化学を決定するポリメトリック分析.
主要な成果:
- 変異酵素L87N;Y290FおよびL87W;Y290Fは, (R) -ヒドロキシ-2-オキシ酸と単独で活性を示した.
- ステレオ補完性アルドラーゼは,4-ヒドロキシ-2-オキシ酸の反対のステレオアイソメールを生成した.
- 触媒効率 (kcat/Km) は,二重変種ではほとんど影響を受けませんでした.
結論:
- ステレオコンプリメンタリークラスIIのピルバートアルドラーゼは成功裏に設計されました.
- これらの酵素は, (S) と (R) の両方のキラル4'-ヒドロキシ-2-オキシ酸骨格へのアクセスを提供します.
- エンジニアリングされたアルドラーゼは,有機合成のための貴重なシントンとして機能します.
関連する概念動画
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