重定向真菌聚基酸合成酶的循环化步骤
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
概括
研究人员通过改变 thioesterase/claisen cyclase (TE/CLC) 域来重定向真菌聚基酸合成酶 (PKS) 循环化步骤. 这使得新型多基基的合成成为可能,并证明了结合真菌和细菌PKS组件的潜力.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 自然产品的合成自然产品的合成
背景情况:
- 聚基化物天然产品是由大型代巨合成酶合成的,主要是在真菌中.
- 在这些大合成酶中,终端硫酶/克莱森环酶 (TE/CLC) 域决定了聚基链的区域选择性循环.
- 了解和操纵这些循环化步骤对于生成新的多基基结构至关重要.
研究的目的:
- 研究用于重定向真菌聚基酸合成酶 (PKSs) 的循环化途径的策略.
- 探索TE/CLC域与PKS大合成酶的功能相互作用.
- 评估结合真菌和细菌PKS组件的可行性,以进行新型聚基化物合成.
主要方法:
- 在Gibberella fujikuroi PKS4.4中,TE/CLC域的非激活或移除.
- 用一个独立的TE/CLC域补充突变PKS4.
- 在多种分离的细菌定制酶的转子添加到大合成酶中.
主要成果:
- TE/CLC域的无活化导致了一个新的多基胺,SMA93 (2) 的合成.
- 补充恢复了区域选择性循环,产生SMA76 (1),证实TE/CLC域功能.
- 添加了细菌酶,如act KR和cyclases,从而产生了突变蛋白 (3) 和 antraquinones (DMAC 5,SEK26 6).
结论:
- TE/CLC域在指导多基化循环中起着至关重要的作用.
- 循环酶可以在转移过程中与PKS大合成酶功能互动.
- 真菌和细菌PKS组件之间的合作活动使得来自不同PKS家族的多种多种类型的合成成为可能.
相关概念视频
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