通过无指的USP类型效应器TssM进行duebiquitination的结构基础
Thomas Hermanns1, Matthias Uthoff2, Ulrich Baumann2
1Institute for Genetics, University of Cologne, Cologne, Germany t.hermanns@uni-koeln.de.
Life science alliance
|January 3, 2024
概括
细胞内细菌使用双基酶 (DUB) 效应器来逃避宿主防御. 研究人员发现了Burkholderia TssM,一种独特的USP级DUB,具有用于无处不在的识别的新"小指"循环.
科学领域:
- 微生物学 微生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 细胞内细菌面临着乌比奎介导的自,这是宿主防御机制.
- 细菌二维基基因酶 (DUB) 效应器对于规避这一过程至关重要.
- 大多数细菌DUB都是OTU或CE族,但Burkholderia物种拥有USP级的TssM效应器.
研究的目的:
- 阐明来自Burkholderia pseudomallei和Burkholderia mallei的TssM效应物的结构和功能.
- 了解TssM独特的无处不在素识别机制,这是USP级细菌DUB.
主要方法:
- 使用X射线晶体学来确定孤立的TssM及其与ubiquitin复合物的结构.
- 结构分析的重点是确定涉及DUB活动和本地化的关键领域和功能区域.
主要成果:
- TssM缺乏典型的"指"子域,这是真核生物USP酶的典型特征.
- 发现了一种新的"小指"循环,它介绍了独特的ubiquitin接口识别.
- 观察到一种能够形成链交换二极体的N端免疫球蛋白折叠域,可能参与细菌表面定位.
结论:
- TssM代表了一种独特的细菌USP类二维基因酶,具有不同的泛基因结策略.
- 新的"小指"循环和免疫球蛋白折叠域突出显示了细菌效应蛋白的进化适应.
- 这些发现提供了细菌破坏宿主免疫力的策略和治疗干预的潜在目标的见解.
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