在Clostridioides difficile中,TcdE霍林驱动毒素分泌和毒性
N V DiBenedetto1, M Oberkampf2, L Cersosimo1
1Massachusetts Host-Microbiome Center, Dept. Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
bioRxiv : the preprint server for biology
|September 25, 2023
概括
霍林TcdE对于Clostridioides difficile毒素的释放和毒性至关重要. 删除TcdE显著减少了毒素分泌,保护小鼠免受致命感染.
科学领域:
- 微生物学 微生物学
- 传染性疾病 传染性疾病
- 细菌病原体的产生
背景情况:
- 困难菌是医疗保健相关感染的主要原因之一.
- 毒素TcdA和TcdB,由病原性位置 (PaLoc) 编码,是关键的毒性因素.
- 这些毒素的释放机制尚未完全理解,因为它们缺乏信号序列.
研究的目的:
- 调查holin TcdE在Clostridioides difficile毒素分泌和毒性中的体内作用.
- 确定TcdE是否对TcdA和TcdB的释放至关重要.
主要方法:
- 在高毒性C. difficile菌株UK1 (核型027) 和VPI10463 (核型087) 中产生了ΔtcdE突变.
- 在体外和体内评估毒素分泌水平.
- 在 gnotobiotic 鼠标感染模型中评估了 ΔtcdE 突变的毒性.
主要成果:
- 与野生型菌株相比,DtcdE突变体表现出严重减少的毒素分泌.
- 从致命的C. difficile感染中拯救的gnotobiotic小鼠中删除tcdE.
- 受 ΔtcdE 突变病毒感染的小鼠表现出细胞外毒素水平降低,粘膜损伤有限,长期存活.
结论:
- TcdE对于C. difficile毒素TcdA和TcdB的体内分泌至关重要.
- TcdE在C. difficile的发病和毒性中发挥着关键作用.
- 向TcdE代表了对抗C. difficile感染的潜在治疗策略.
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