基因组降解通过重塑纤维膜介导的炎症反应来促进沙门氏菌的病变适应
Xiao Zhou1,2, Xiamei Kang1, Jiaqi Chen1
1Institute of Preventive Veterinary Sciences and Department of Veterinary Medicine, Zhejiang University College of Animal Sciences, Hangzhou 310058, China.
National science review
|November 15, 2023
概括
沙门氏菌Pullorum通过降解fimbriae进化,增强毒性和切换到家禽的垂直传播. 这种细菌适应影响了禽业的疾病管理.
科学领域:
- 微生物学 微生物学
- 进化生物学 进化生物学
- 基因组学就是基因组学.
背景情况:
- 病原体基因组降解是一种已知的进化策略.
- 基因组降解在改变病原体行为和传播方面的具体作用尚不清楚.
- 了解这些变化对于管理新出现的传染病至关重要.
研究的目的:
- 调查基因组降解在鸟类受限型沙门氏菌 (Salmonella Pullorum,bvSP) 进化中的作用.
- 通过时间分析bvSP血统的遗传多样性和毒性.
- 阐明bvSP适应和改变传播背后的分子机制.
主要方法:
- 对超过一个世纪的鸟类受限沙门氏菌基因组进行了基因组学分析.
- 在和胚胎中进行感染测定,以评估毒性.
- 全基因组分析以识别遗传变化,包括手足基因降解.
- 电影删除突变体的工程研究传播动态.
主要成果:
- 确定了三种bvSP血统,最近的血统中毒性增加 (L2/L3).
- 祖先血统 (L1) 显示出更大的代谢灵活性和环境耐受性.
- 骨基因降解与从水平传播到垂直 (跨卵巢) 传播的转换有关.
- bvSP表现出持续复制与减少了巨细胞的炎症.
结论:
- 基因组降解,特别是手指骨的损失,是bvSP的关键适应策略.
- 这种重塑增强了毒性,并促进了垂直传播,与家禽业的强化保持一致.
- 细菌表面附属体改造的新型范式补充了有效的垂直传播的毒性进化.
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