一种细菌间毒素通过合成 (p)ppApp来抑制目标细胞的生长
Shehryar Ahmad1,2, Boyuan Wang3, Matthew D Walker2
1Michael DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada.
Nature
|November 8, 2019
概括
使用一种新型毒素Tas1,通过VI型分泌系统诱导竞争细胞死亡. Tas1产生 (p) pApp,破坏新陈代谢并耗尽ATP.
科学领域:
- 微生物学
- 细菌致病性
- 分子生物学
背景情况:
- 细菌采用各种策略,包括第六类分泌系统 (T1SS),以对抗竞争对手.
- T1SS效应器通常针对细胞包膜完整性,但其他增长抑制机制的理解较少.
- 在压力下,信号分子 (p) pGpp 调节细菌生长.
研究的目的:
- 在Pseudomonas aeruginosa中识别和描述新的T1SS效应体.
- 阐明已识别的Tas1效应物的作用机制.
- 研究代谢物 (p) ppApp在细菌抗性的作用.
主要方法:
- 测定Tas1的晶体结构
- 酶测试以确定Tas1的活性.
- 在Tas1输送时对目标细胞进行代谢分析.
- 细胞活力和代谢途径的评估.
主要成果:
- 鉴定了P. aeruginosa的一种T1SS效应体Tas1.
- Tas1表现出高酸酶活性,从腺核酸中产生 (p) pApp.
- 传递Tas1导致目标细胞中的快速 (p) pApp积累,ATP耗尽和代谢失调.
- 这导致竞争细菌的快速细胞死亡.
结论:
- 描述了一种由Tas1和 (p) pApp介导的新型细菌间对抗机制.
- Tas1 是一种针对核酸代谢的新型细菌毒素.
- (p) ppApp被认为是细菌竞争中的关键代谢物.
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