贝耶-维利格单氧化酶催化细菌类核结构成熟的产品选择性
在PubMed上查看摘要
概括
此摘要是机器生成的。像BraC和PxaB这样的Baeyer-Villiger单氧酶 (BVMOs) 从相同的中间体中产生不同的自然产物. 这项研究显示,BraC控制了布拉本胺的形成,而PxaB的选择性取决于基质结构.
科学领域
- 生物化学和酶学
- 自然产品的生物合成
- 有机化学
背景情况
- 贝耶-维利格单氧酶 (BVMOs) 是修改自然产品核心结构的关键酶.
- 细菌BVMOs BraC和PxaB处理二英多利津基质,形成一种oxazepine-dione中间体.
- 尽管有共同的中间体,但BraC产生了布拉本胺,而PxaB产生了 pyrrolizixenamides,其选择性因子以前是未知的.
研究的目的
- 阐明控制BraC和PxaB催化反应产品选择性的因素.
- 了解天然产品生物合成中常见中间体的产品形成途径.
主要方法
- 关键途径中间体和预期的天然产品的总合成.
- 使用重组BraC和PxaB酶进行的体外功能研究.
- 对反应机制和产品形成途径的分析.
主要成果
- 通过水解,脱碳化和脱水,共享的氧泽二烯中间体非酶化转化为氧化.
- 布拉本胺的生物合成是受酶控制的,BraC有效地将基质转化为相关产品.
- PxaB仅在模仿天然布拉班塔胺侧链的基质类型中表现出显著的布拉班塔胺形成活性,这表明基质受控制的选择性.
结论
- 在这种BVMO系统中,产品的选择性由酶标识和基质结构决定.
- 而PxaB的产物结果则通过基质识别来调节.
- 这项研究阐明了同类BVMOs形成不同的自然产品的机制基础.
相关概念视频
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