分子架构和电子转移途径的Stn家族的transhydrogenase
Anuj Kumar1,2, Florian Kremp2, Jennifer Roth2
1SYNMIKRO Research Center and Department of Chemistry, Philipps-University of Marburg, Marburg, Germany.
Nature communications
|September 6, 2023
概括
对于无氧代谢至关重要的Stn转酶复合体,利用独特的分叉模块来节能. 它的结构揭示了模块化的进化,使其能够在生命的热力学极限下生存.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 微生物学 微生物学
- 代谢工程是代谢工程.
背景情况:
- 电子分支是无氧代谢中节能的关键,特别是在伍德-Ljungdahl路径中.
- 像Nfn复合体一样,依赖于铁素的转基因酶促进了使用NADH减少NADP.
- 最近已经确定了一个与Nfn类型分开的独特的Stn转酶复合体.
研究的目的:
- 阐明来自*Sporomusa ovata*的Stn家族转酶的结构和功能.
- 了解Stn复合体内的电子转移途径和进化适应.
- 为了比较Stn复合物与其他已知的二分化转化化酶.
主要方法:
- 单粒子冷电子显微镜 (cryo-EM) 用于结构的确定.
- 功能分析来剖析电子转移路径.
- 与同类复合体进行比较结构分析.
主要成果:
- 该Stn复合体形成一个四聚体的异构三聚体StnABC单元.
- StnAB子单元作为一个分叉模块,同类于HydBC.
- StnC拥有类似NuoG和类似GltD的NADPH结合域,但缺乏分支活动,与NfnB不同.
结论:
- Stn复合体体现了无氧代谢的模块化进化,适应蛋白质折叠以实现不同的功能.
- 这种模块化允许在极端热力学条件下实现生存的关键活动.
- 这些发现提供了关于古代代谢途径中节能多样化的进化策略的见解.
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