一种类似于ubiquitin的蛋白质控制了细菌类型VIIb分泌系统的组合
Gabriel U Oka1, Nathanaël Benoit1, Axel Siroy1,2
1CNRS UMR 5234 Microbiologie Fondamentale et Pathogénicité, Institut Européen de Chimie et Biologie, University of Bordeaux, 33600 Pessac, France.
Science advances
|November 21, 2025
概括
第七类分泌系统 (T7SS) 对细菌毒性至关重要. 这项研究揭示了YukD蛋白如何作为Bacillus subtilis.类型VIIb分泌系统 (T7SSb) 的关键组装器.
科学领域:
- 微生物学 微生物学
- 结构生物学 结构生物学
- 分子生物学分子生物学
背景情况:
- 第七类分泌系统 (T7SS) 是格拉姆阳性细菌中必不可少的蛋白质载体,在毒性和细菌间竞争中发挥作用.
- 在Firmicutes中普遍存在的VIIb型分泌系统 (T7SSb) 组装的基础结构机制尚不清楚.
研究的目的:
- 阐明组装VIIb型分泌系统 (T7SSb) 核心复合物的结构基础.
- 了解乌比奎类蛋白 YukD 在 T7SSb 组装和功能中的作用.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定来自Bacillus subtilis的T7SSb核心复合物的结构.
- 时间间隔显微镜和细菌竞争试验被用来评估YukD.的功能意义.
主要成果:
- 冷-EM结构显示,YukD通过与通道组件YukB和伪激酶YukC的相互作用来协调T7SSb机械的组装.
- YukD有助于形成一个稳定的构建块,这对于分泌道至关重要.
- YukD被证明对T7SSb复合物的正确形成和接触依赖的细菌杀死至关重要.
结论:
- 细菌利用类似于乌比奎丁的蛋白质,如YukD,作为结构调节剂,用于组装T7SSb.等大型分泌复合体.
- 这项研究为控制T7SSb组装和功能的分子机制提供了新的见解,突出了YukD的关键作用.
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