FliO是细菌鞭毛型III分泌系统的进化保守但多样化的核心组成部分
Ekaterina P Andrianova1, Amanda L Dobbins2, Marc Erhardt3,4
1Department of Microbiology, The Ohio State University, Columbus, Ohio, USA.
bioRxiv : the preprint server for biology
|July 14, 2025
概括
FliO是细菌鞭毛的关键,古老的组成部分,对于机动性和宿主殖民至关重要. 这项研究揭示了它在各种细菌物种中广泛存在和功能性可塑性.
科学领域:
- 微生物学 微生物学
- 进化生物学 进化生物学
- 结构生物学 结构生物学
背景情况:
- 细菌鞭毛对细菌的功能至关重要,如机动性和宿主殖民.
- 像FliO这样的蛋白质的作用,注释不一致和低序列保存,一直不清楚.
- 之前对细菌基因组中鞭状基因流行率的估计可能不准确.
研究的目的:
- 为了对FliO蛋白进行全面的基因组学和结构分析.
- 为了澄清FliO在细菌分泌系统中的进化和功能意义.
- 为了研究鞭毛基因和FliO组件在多种细菌群中的流行情况.
主要方法:
- 在超过3万个细菌基因组中对FliO进行了基因组学分析.
- 使用HMM搜索和操作上上下文分析的定制生物信息管道.
- 在 *Campylobacter jejuni* 中进行了FliO的结构分析和功能研究.
主要成果:
- FliO存在于约95%的编码核心鞭毛成分 (FliP,FliQ,FliR) 的基因组中,这表明它是鞭毛类型III分泌系统 (fT3SS) 几乎无处不在的祖先组成部分.
- 大约40%的细菌基因组含有鞭毛基因,比以前估计的更低的患病率.
- FliO表现出显著的结构多样性,与谱系特定的域 (LysM,AMIN) 和在非鞭毛系统中发现的同类,表明功能重新利用.
- 在 *Campylobacter jejuni* 的功能研究表明,FliO 在双极鞭,FlhB 稳定性和宿主殖民化中的关键作用.
结论:
- FliO是细菌鞭毛和鞭毛类型III分泌系统的进化动态但核心组成部分.
- 这些发现为细菌分泌系统的演变和多样化提供了新的见解.
- FliO的功能可塑性超出了鞭毛组合,影响了细菌的毒性和适应性.
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