由专用聚基化合成模块催化维尼洛基链分支
Tom Bretschneider1, Joel B Heim, Daniel Heine
1Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena 07745, Germany.
Nature
|September 20, 2013
概括
科学家们发现了一种新的细菌酶模块,可以在多基基中创建分支碳链,从而扩大药物发现的可能性. 这种新的机制与已知的途径不同,对于强大的抗癌和抗真菌化合物的活性至关重要.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 合成生物学 合成生物学
背景情况:
- 模块化多基酸合成酶 (PKSs) 对于产生复杂的多基酸酶至关重要,许多用于抗感染和抗瘤药物的道.
- 目前的PKS研究主要集中在线性骨干组装上,限制了多基化合物的结构多样性.
- 对PKS路径的合理工程对于产生新药类型来说至关重要.
研究的目的:
- 为了研究来自Burkholderia rhizoxinica的新型PKS模块,具有独特的链分支能力.
- 阐明这种非正规的多基基组件的机制及其结构基础.
- 探索这项发现对产生多基虫的结构多样性的影响.
主要方法:
- 在PKS模块的体外复制.
- 关键领域的X射线晶体学.
- 现场指导的突变发生实验.
- 中间状态的分析.
主要成果:
- 确定了一种新的PKS模块,能够进行迈克尔类型的乙添加,从而在多基基链中创建一个分支.
- 合成酶域被确定为这种分支活动的关键.
- 一个共价连接的中间状态揭示了一种新的链化机制,与类分支不同.
- 这种非正规的修改对于强有力的抗真菌剂里佐辛的生物活性至关重要.
结论:
- 该研究揭示了一种新的PKS模块和机制,扩大了聚基化组装的生物合成范围.
- 这一发现为理性地设计PKS路径提供了基础,以创建具有治疗潜力的新型多基基结构.
- 拟议的vinylogous分支反应为PKS模块提供了一个统一的模型,具有合成酶分支-酸载体-蛋白质架构.
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