通过激进的SAM酶对RiPP进行表皮化的结构和机制基础
Xavier Kubiak1, Ivan Polsinelli1, Leonard M G Chavas2
1Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, ChemSyBio, Jouy-en-Josas, France.
Nature chemical biology
|December 29, 2023
概括
D-氨基酸对于的生物活性至关重要. 激进的SAM酶催化它们在RiPPs中的形成,这项研究揭示了它们的结构和表化机制.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 酶学 是一种酶学.
背景情况:
- D-氨基酸残留对许多的生物活性至关重要,包括抗生素和毒素.
- 核糖体合成和翻译后修改的 (RiPPs) 通常含有D-氨基酸.
- 激进的S-adenosyl-L-methionine (SAM) 酶是唯一已知的生物催化剂,用于RiPPs的直接表皮化,但它们的机制尚不清楚.
研究的目的:
- 阐明激进SAM酶在RiPP中安装D-氨基酸的机制和结构基础.
- 为了确定一个RiPP修饰激素SAM酶及其基质的原子分辨率结构.
主要方法:
- 用X射线晶体学来确定原子分辨率结构.
- 尺寸排除色谱-小角度X射线散射 (SEC-SAXS) 用于结构分析.
- 电子磁共振 (EPR) 光谱用于机械洞察力.
- 生物化学分析以验证酶功能.
主要成果:
- 确定了与其基质结合的RiPP修饰激素SAM酶的原子分辨率晶体结构.
- 结构和生化数据揭示了RiPPs中的表皮化机制.
- 提出了一种前所未有的皮质表皮化酶机制.
结论:
- 这项研究提供了关于激进SAM酶如何与RiPPs相互作用的关键见解.
- 这些发现有助于我们更好地理解自然产品生物合成中的翻译后修改.
- 阐明的机制为激进SAM酶催化提供了新的视角.
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