菌類のポリケチド合成酵素のサイクル化のステップをリダイレクトする
Suzanne M Ma1, Jixun Zhan, Xinkai Xie
1Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, California 90095, USA.
Journal of the American Chemical Society
|December 13, 2007
まとめ
研究者らは,チオエステラゼ/クライスンサイクラゼ (TE/CLC) ドメインを変更することで,真菌ポリケチド合成酵素 (PKS) サイクル化のステップをリダイレクトした. これにより,新しいポリケチドの合成が可能になり,真菌と細菌のPKS成分を組み合わせる可能性が示されました.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 自然製品合成 自然製品合成
背景:
- ポリケチドの天然産物は,主に真菌の大きな反復メガシンタゼによって合成されます.
- これらのメガシンタゼ内のターミナル・チオエステラーゼ/クライスン・サイクラゼ (TE/CLC) ドメインは,ポリケチド鎖の地域選択的サイクリングを決定する.
- これらのサイクル化のステップを理解し,操作することは,新しいポリケチド構造を生成するために不可欠です.
研究 の 目的:
- 菌類のポリケチド合成酵素 (PKSs) のサイクリング経路をリダイレクトするための戦略を調査する.
- PKSメガシンタゼとTE/CLCドメインの機能的相互作用を探求する.
- 新しいポリケチド合成のために,真菌と細菌のPKS成分を組み合わせることの実現可能性を評価する.
主な方法:
- Gibberella fujikuroi PKS4.のTE/CLCドメインの不活性化または除去について
- 変異したPKS4を独立したTE/CLCドメインで補完する.
- メガシンタゼに様々な分離した細菌の調整酵素をトランス添加する.
主要な成果:
- TE/CLCドメインの不活性化により,新しいポリケチドSMA93 (2) が合成されました.
- コンプリメンテーションにより,地域選択的サイクルが復元され,SMA76 (1) が得られ,TE/CLCドメインの機能が確認されました.
- act KRやcyclasesなどのバクテリア酵素を加えることで,ミュータクチン (3) とアントラキノン (DMAC 5,SEK26 6) が生成される.
結論:
- TE/CLCドメインは,ポリケチドサイクルを誘導する上で重要な役割を果たします.
- サイクリング酵素は,PKSメガシンタゼとトランスで機能的に相互作用することができます.
- 菌類と細菌のPKS成分間の協力活動は,異なるPKSファミリーから多様なポリケチドの合成を可能にします.
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