压力诱导的铁硫集群损伤作为细菌严格反应的保存触发器
Eva Michaud1, Lorena Ricci2, Claire Lallement1
1INSERM U1230, University of Rennes, Rennes, France.
Nature communications
|March 2, 2026
概括
铁硫集群损伤会触发致病细菌的严格反应,影响氨基酸水平并激活RelA. 这种反应在宿主感染期间增强了细菌的健康和毒性.
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:
- 病原细菌利用严格的反应来生存宿主施加的压力.
- 对于宿主诱导的严格响应激活的确切触发因素尚未完全理解.
研究的目的:
- 为了确定格拉姆阴性病原体中严格反应的保存触发因素.
- 阐明铁硫集群损伤在激活这种反应中的作用及其对毒性的影响.
主要方法:
- 研究了氧化应激和金属不平衡对铁硫集群完整性的影响.
- 评估了 (p)ppGpp合成酶RelA的激活及其下游效应.
- 在压力条件下分析了沙门氏菌SPI-2型III分泌系统的调节.
主要成果:
- 确定铁硫 (Fe-S) 集群损伤是沙门氏体,Enterobacter cloacae和Klebsiella pneumoniae严格反应的保存触发因素.
- 证明Fe-S集群破坏导致有限的含硫和分支链氨基酸,激活RelA.
- 通过调节沙门氏菌SPI-2型III分泌系统,证明 (p) p Gpp增强了细菌的健康状况,并促进了毒性.
结论:
- Fe-S 集群完整性是病原性细菌中宿主相关压力的关键传感器.
- 由Fe-S集群损伤引发的严格反应在促进细菌健康和毒性方面发挥了双重作用.
- 这种机制突出了在感染期间将环境线索整合到适应性反应的保护途径.
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