基于结构的洞察力,了解依赖4Fe-4S的硫插酶LarE的机制
Paolo Zecchin1, Ludovic Pecqueur1, Jonathan Oltmanns2
1Laboratoire de Chimie des Processus Biologiques, Collège de France, CNRS UMR 8829, Sorbonne Université, Paris cedex 05, France.
Protein science : a publication of the Protein Society
|December 15, 2023
概括
研究人员阐明了一种硫插酶酶Methanococcus maripaludis LarE的结构,揭示了在必需代谢物生物合成中硫转移的新型 [4Fe-4S] 集群机制.
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:
- 重要的细胞代谢物,包括酶辅因子,含有硫原子,对生物过程至关重要.
- 含硫代谢物的生物合成依赖于特定的硫化酶.
- 拉尔E酶是依赖ATP的硫插入酶,对于将碳酸盐转化为硫酸盐至关重要.
研究的目的:
- 为了确定Methanococcus maripaludis LarE (MmLarE) 的晶体结构,一个 [4Fe-4S] 集群依赖的硫插酶.
- 阐明 [4Fe-4S] 集群在硫转移中的作用的结构基础.
- 将MmLarE结构与不同类别的先前解决的LarE酶进行比较.
主要方法:
- 通过X射线晶体学,以apo (无集群) 和holo (集群结合) 形式获得MmmLarE的结构.
- 对Holo-MmLarE进行了光谱分析.
- 结构数据与相关酶的现有生物化学数据相结合.
主要成果:
- Holo-MmLarE的晶体结构揭示了由三个半氨酸协调的 [4Fe-4S] 集群,留下一个开放的铁协调部位.
- 这个开放的位置可以结合离子连接物,如酸盐或化物.
- 该结构支持一个机制,其中 [4Fe-4S] 集群结合硫化物,形成 [4Fe-5S] 介质,用于基质硫化.
结论:
- MmLarE的结构为 [4Fe-4S] 集群依赖硫转移的机制提供了关键的见解.
- 这种机制类似于其他依赖 [4Fe-4S] 的tRNA硫化酶.
- 这些发现推动了我们对硫代谢和酶辅因子生物合成的理解.
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