霍乱病毒 (Vibrio cholerae) 整合了跨物种的定数感应信号,以调节毒性
Erick Maosa Bosire1, Myfanwy C Adams2, Paulina D Pavinski Bitar1
1Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
mBio
|July 31, 2025
概括
肠道细菌发出的信号,称为扩散信号因子 (DSF),可以抑制Vibrio cholerae的毒性. 这些信号准了调节器ToxT,通过破坏病原体的毒性来提供控制霍乱的新方法.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 病原体与宿主之间的相互作用
背景情况:
- 人的肠道微生物组显著影响化学环境.
- 霍乱病毒适应肠道环境,在特定的肠道中激活毒性因素.
- 了解病原体-微生物群相互作用对于开发针对肠道病原体的新型控制措施至关重要.
研究的目的:
- 研究Vibrio cholerae如何感知和响应肠道化学信号,特别是扩散信号因子 (DSF).
- 阐明DSFs调节关键毒性因子,霍乱毒素 (ctxAB) 和毒素共同调节的毒素 (tcpA-F) 的表达机制.
- 为了确定DSF的特定化学特性,负责它们对毒性进行监管活动.
主要方法:
- 评估了各种DSF对V. cholerae中ctxAB和tcpA-F表达的影响.
- 使用生化和遗传方法研究了DSFs和转录调节器ToxT之间的相互作用.
- 确定了DSF的结构-活性关系,重点关注碳链长度,双键位置和碳酸末端.
主要成果:
- 发现扩散信号因子 (DSF) 抑制了依赖ToxT的毒性因子ctxAB和tcpA-F的表达.
- 鉴定出cis-2-hexadecenoic acid (c2HDA) 是一种强大的DSF,可以抑制ctxAB的84倍和tcpA-F的12倍.
- DSF与ToxT相互作用,抑制其DNA结合并促进其降解,特定的化学特征增强了这种效应.
结论:
- 霍乱杆菌集成来自肠道微生物群的跨物种DSF信号,以控制毒性因子表达.
- DSFs,特别是c2HDA,针对ToxT的脂肪酸结合口袋,导致抑制的毒性.
- 这些发现为开发针对V. cholerae的干预措施提供了一个框架,通过针对DSF介导的毒性调节来开发干预措施.
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