(p) 对于Shigella flexneri的毒性,ppGpp是必要的
Grace Kago1, Charles L Turnbough2, Juan Carlos Salazar3
1Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, USA.
Infection and immunity
|December 15, 2023
概括
破坏Shigella flexneri中严格响应激素 (p) pGpp的干扰显著降低了毒性基因表达,细菌入侵和传播. SpoT对于Shigella flexneri的发病和细胞内适应是必不可少的.
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:
- 菌 (Shigella flexneri) 侵入宿主结肠上皮,面临着压力的细胞内环境.
- 细菌适应宿主细胞细胞醇需要显著的生理变化.
研究的目的:
- 调查严格响应警报激素 (p)ppGpp在Shigella flexneri毒性的作用.
- 确定RelA和SpotT对 (p) pGpp合成和病原学的贡献.
主要方法:
- 在S. flexneri. 中对 (p) pGpp合成基因 (relA和spoT) 的遗传破坏.
- 在试验室中评估病毒性基因表达,细菌入侵和细胞间传播.
- 评估斑块形成和补充试验.
主要成果:
- 破坏 (p)ppGpp合成减少了关键的毒性基因 (ipaA,ipaB,ipaC,icsA) 并减少了入侵和传播.
- 单独删除relA没有效果,但relA spoT的双重删除取消了 (p) pGpp合成和毒性.
- 在relA spoT突变显示减少入侵和失败的细胞间传播,与SpoT补充恢复斑块形成.
结论:
- 严格的响应警报激素 (p) ppGpp对于S. flexneri的毒性至关重要.
- SpoT足以维持致病发生所需的 (p) pGpp水平.
- (p) pGpp对于S. flexneri适应细胞内环境和在宿主组织中传播至关重要.
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