在较高的细胞密度下,Yersinia 活跃下调III型分泌和粘附
Francesca Ermoli1, Gabriele Malengo2,3, Christoph Spahn4,5
1Department of Ecophysiology, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany.
PLoS pathogens
|August 12, 2025
概括
在高细胞密度下,Yersinia细菌积极抑制III型分泌系统 (T3SS) 的注射体. 这种由VirF进行的调节会影响毒性和细菌粘附,促进复制而不是殖民.
科学领域:
- 微生物学 微生物学
- 细菌病原体的产生
- 分子生物学分子生物学
背景情况:
- 格拉姆阴性细菌利用III型分泌系统 (T3SS) 的注射体来向真核细胞输送效应蛋白.
- 以前,人们认为T3SS模型生物体Yersinia enterocolitica可以构成性地表达和组装注射体.
研究的目的:
- 研究不同细胞密度的Yersinia enterocolitica中T3SS表达,组合和活性的调节.
- 阐明T3SS抑制背后的分子机制及其功能后果.
主要方法:
- 在不同的细菌密度下分析T3SS基因表达和蛋白质组合.
- 对T3SS转录因子VirF的基因操纵.
- 评估细菌粘附和T3SS活动.
主要成果:
- Yersinia enterocolitica在更高的细胞密度下,如微殖民地内,积极抑制T3SS注射体的表达,组合和活性.
- 这种抑制是由主要的T3SS转录因子VirF.F.的下调调节介导的.
- 病毒F下调还导致粘附蛋白YadA的表达减少,减少细菌细胞粘附.
- 通过在转换中表达VirF,可以恢复T3SS活动.
结论:
- 在高细胞密度下,Yersinia enterocolitica采用活性T3SS抑制,这种机制与静止相适应有所区别.
- 这种受管制的抑制促进了从T3SS依赖的殖民阶段过渡到感染期间的复制和传播阶段.
- 这些发现揭示了一种新的细菌病原体调节策略,影响细菌与宿主相互作用.
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