一种细菌分泌的糖酶增强了对肠道病原体的耐受性
Kavita J Rangan1, Virginia A Pedicord2, Yen-Chih Wang3
1Laboratory of Chemical Biology and Microbial Pathogenesis, The Rockefeller University, New York, NY 10065, USA. krangan@rockefeller.edu hhang@rockefeller.edu.
概括
从Enterococcus faecium分泌的抗原A (SagA) 通过增强病原体耐受性来保护沙门氏菌. 这种细菌蛋白及其碎片提供了保护,提高了模型生物的益生菌有效性.
科学领域:
- 微生物学
- 免疫学
- 宿主-病原体相互作用
背景情况:
- 肠道微生物组影响宿主对肠道病原体的防御.
- 提供保护的特定细菌因素尚未完全理解.
- 肠杆菌是一种常见的肠道共生菌,具有潜在的保护作用.
研究的目的:
- 为了确定Enterococcus faecium对沙门氏菌的保护因素.
- 阐明这些因素赋予保护的机制.
- 探索这些因素在增强益生菌疗法的潜力.
主要方法:
- 用 Caenorhabditis elegans 作为一个模型生物来研究宿主-病原体相互作用.
- 研究了来自E. faecium的分泌抗原A (SagA) 的作用.
- 评估了SagA的NlpC/ p60糖酶活性.
- 产生并测试保护作用的muramyl片段.
- 在益生菌中检查 SagA 的异质表达.
- 在C. elegans和小鼠模型中评估了保护作用.
主要成果:
- Enterococcus faecium所分泌的抗原A (SagA) 足以保护C. elegans免受沙门氏菌感染.
- 通过促进宿主病原体的耐受性,SAGA提供了保护.
- 对于保护而言,Saga的NlpC/ p60基酶活性至关重要.
- 从Saga生成的muramyl片段足以以tol-1依赖的方式保护C.elegans.
- 在C. elegans和小鼠中,SagA的异构表达增强了对沙门氏菌的益生菌保护.
结论:
- 从E. faecium分泌的抗原A (SagA) 是赋予病原体耐受性的关键因素.
- SagA 的酶活性会产生保护分子 (muramyl-peptides).
- SagA代表了开发新策略来对抗肠道感染和增强益生菌有效性的有希望的目标.
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