为了形成非正规的VI型分泌系统尖端复合体,需要保存的伴侣蛋白
Kartik Sachar1, Katarzyna Kanarek2, Jake Colautti3
1Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada; Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada.
The Journal of biological chemistry
|January 29, 2025
概括
DUF2169蛋白质作为VI型分泌系统 (T6SS) 尖端综合体的新型护理者. 它们确保VgrG-PIPY复合体准备分泌,揭示了对细菌毒素输送机制的新见解.
科学领域:
- 微生物学 微生物学
- 结构生物学 结构生物学
- 细菌病原体的产生
背景情况:
- 六型分泌系统 (T6SS) 对于格拉姆阴性细菌来说是必不可少的,它们可以将效应蛋白传递到细胞中.
- T6SS辅助蛋白对于效应器加载至关重要,但它们的功能往往是未知的.
- DUF2169 蛋白家族是 T6SS 辅助蛋白质的一个鲜明的特征组.
研究的目的:
- 描述DUF2169蛋白家族并阐明它们在T6SS功能中的作用.
- 了解DUF2169蛋白和T6SS尖端复合体之间的相互作用.
- 为了确定DUF2169函数的结构基础.
主要方法:
- 基因并发分析以确定相互作用的T6SS组件.
- 基因和生物化学测试来测试蛋白质相互作用和功能.
- 进行X射线晶体学以确定DUF2169蛋白质的结构.
- 生物物理和结构建模以分析蛋白质与蛋白质相互作用.
主要成果:
- DUF2169基因与VgrG和DUF4150 (P যুক্তিPY) 域同时发生,形成T6SS尖峰复合体.
- 功能性VgrG-P যুক্তিPY尖峰复合体形成需要DUF2169蛋白质,与正规的PAAR蛋白质不同.
- DUF2169的晶体结构揭示了一个新的折叠,具有与PIPY域相互作用的动态循环.
- DUF2169蛋白质的功能是陪伴者,保持尖端复合体在分泌竞争状态.
结论:
- 在T6SS中,DUF2169蛋白是VgrG-P যুক্তিPY尖端复合体的必不可少的陪伴者.
- 这项研究揭示了一种调节T6SS效应体分泌的新机制.
- 这些发现为T6SS辅助蛋白质多样性提供了结构和功能洞察力.
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