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A Visual Assay to Monitor T6SS-mediated Bacterial Competition
Published on: March 20, 2013
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描述E. cloacae SBP-8的6型分泌系统 (T6SS) 以及其在病原和细菌竞争中的作用
Shahid Khan1, Sandhya Amol Marathe2, Prabhat Nath Jha2
1Department of Biomedical Engineering, University of California Davis, Davis, CA, USA; Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Pilani, 333031, Rajasthan, India.
Microbial pathogenesis
|August 3, 2023
概括
环境病原体E.cloacae SBP-8中的VI型分泌系统 (T6SS) 对于与其他细菌竞争至关重要. 然而,这种T6SS并不能促进病原体侵入或在宿主细胞内生长的能力.
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 (E. cloacae) 是一种机会性病原体,其毒性机制尚不清楚.
- 六型分泌系统 (T6SS) 是许多细菌中已知的毒性因子,但其在E.cloacae中的作用尚不清楚.
研究的目的:
- 为了研究T6SS在环境中所扮演的角色孤立E.cloacaeSBP-8关于真核生物和细菌相互作用.
- 确定T6SS是否有助于宿主模型中的E.cloacae SBP-8致病性及其对其他细菌的竞争力.
主要方法:
- 基因组测序以识别T6SS基因集群.
- 检测Hcp效应蛋白和评估ClpV-依赖的分泌,以确认功能性T6SS.
- 在Caenorhabditis elegans感染模型中删除与T6SS相关的clpV基因和评估E.cloacaeSBP-8.
- 对宿主免疫基因表达的分析 (clec-60,clec-85,clec-87,lys-1,toll-1).
- 评估细菌入侵,宿主细胞中的增殖,以及巨细胞的细胞化.
- 对抗大肠杆菌 (Escherichia coli) 的细菌间竞争的评估.
主要成果:
- E. cloacae SBP-8具有完整且功能性的T6SS,由基因群分析,Hcp分泌和ClpV依赖证实.
- 干扰T6SS并没有影响E. cloacae SBP-8的生存,C. elegans的殖民或宿主免疫反应.
- 在宿主肠道细胞内,T6SS没有参与E.cloacae SBP-8的入侵或扩散,也没有参与对巨细胞灭菌的抵抗.
- E. cloacae SBP-8的超越大肠杆菌竞争的能力依赖于其T6SS以接触依赖的方式.
结论:
- 环境中孤立的E. cloacae SBP-8中的T6SS对于细菌间的竞争至关重要.
- 在研究的模型中,E. cloacae SBP-8的T6SS在宿主细胞入侵,增殖或毒性方面没有发挥显著作用.
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