快速演变的孤儿免疫基因保护人类肠道细菌免受VI型分泌系统中毒
Amirahmad Azhieh1,2, Paul Hernandez3, Alexander C Anderson1,2
1Michael DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, L8S 4K1, Canada.
bioRxiv : the preprint server for biology
|July 14, 2025
概括
细菌使用像RAID这样的防御系统来幸存于其他细菌的毒性攻击. 这些系统对VI型分泌系统 (T6SS) 进行保护,对人类肠道中的细菌健康至关重要.
科学领域:
- 微生物学 微生物学
- 细菌遗传学 细菌遗传学
- 进化生物学是进化的生物学.
背景情况:
- 细菌使用有毒的效应蛋白来进行细菌间的对抗作用,VI型分泌系统 (T6SS) 是一个关键的传递机制.
- 与复合酶相关的获得性细菌间防御 (rAID) 系统通过不同的孤儿免疫基因提供免疫力,但其功能和生态动态尚不清楚.
研究的目的:
- 为了研究RAID孤儿免疫基因序列分歧的功能影响.
- 探索RAID系统与微生物组中的T6SS分布之间的关系.
- 了解RAID孤儿免疫在人类肠道中的进化动态和健康贡献.
主要方法:
- 生物化学测试用于评估RAID孤儿免疫因子和T6SS效应因子之间的蛋白质-蛋白质相互作用.
- 对人类肠道元基因组数据的生物信息分析,以量化基因丰度和共发生.
- 对纵向元基因组数据的种群遗传分析,以推断选择压力.
主要成果:
- 与 SUKH 域分离的 rAID 孤儿免疫因子通过高亲和相互作用来保护对相关的 T6SS 效应因子.
- 保护接口涉及具有显著冗余性的静电相互作用.
- rAID和T6SS基因在人类肠道元基因组中表现出同时发生的模式,这表明积极选择.
- 纵向数据表明,在孤儿免疫基因的效应器免疫接口上,非同名突变的积累.
结论:
- rAID孤儿免疫提供了有效的细菌防御T6SS中毒.
- 独特的静电结合接口突出了效应器免疫识别的新机制.
- rAID孤儿免疫基因是细菌健康的重要决定因素,并且在人类肠道微生物群中处于积极选择状态.
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