霍乱毒素促进病原体从宿主中获取营养
Fabian Rivera-Chávez1, John J Mekalanos2
1Department of Microbiology, Harvard Medical School, Boston, MA, USA.
Nature
|August 2, 2019
概括
由Vibrio cholerae产生的霍乱毒素 (CTX) 造成缺铁的肠道环境. 这种利基增强了病原体的生长,使细菌能够利用宿主衍生的血和脂肪酸进行营养.
科学领域:
- 微生物学
- 传染性疾病
- 细菌致病性
背景情况:
- 这是一种严重的腹疾病.
- 霍乱毒素 (CTX) 对严重疾病和病原体传播至关重要.
- 霍乱病毒在肠道中达到高度的机制尚未完全理解.
研究的目的:
- 调查V.霍乱如何在感染期间在肠道中达到高度.
- 阐明霍乱毒素 (CTX) 在V. cholerae肠道殖民和生长中的作用.
- 在宿主肠道环境中识别V. cholerae的代谢适应.
主要方法:
- 在感染期间对V. cholerae进行转录组分析.
- 对V. cholerae铁获取途径 (血和振动蛋白) 的遗传分析.
- CTX诱导的乳房病理与代谢物和营养素的可用性相关.
主要成果:
- CTX诱导了一种转录的特征, 表明肠道缺铁.
- 只有在产生CTX时,血和振动菌素获得铁的基因才会产生生长优势.
- 由CTX诱导的膜拥堵增加了血液的生物可用性,并改变了血液中的代谢物 (脂肪酸,L-乳酸).
- 病原体的生长取决于CTX产生的菌株的血液和脂肪酸吸收.
结论:
- CTX诱导的疾病会在肠道中形成一个缺铁的代谢.
- 通过获得宿主衍生的血红和脂肪酸,这种利基选择性地促进了V. cholerae的生长.
- 了解这种机制是控制霍乱病变的关键.
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