通过IVA型分泌系统效应器进行定数火
Jinxing Liao1, Zihan Li1, Dan Xiong1
1College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, Nanjing, China.
The ISME journal
|June 20, 2023
概括
一种新的细菌机制使用效应器转位来阻止乙同素乳 (AHL) 的产生,从而赋予了竞争优势. 这一发现提供了新的策略,通过扰乱定数感应来控制细菌感染.
科学领域:
- 微生物学 微生物学
- 细菌的传播 细菌的传播
- 分子生物学分子生物学
背景情况:
- 蛋白质细菌使用乙同素乳 (AHLs) 进行定数感知,这对于病原体感染至关重要.
- 酶性AHL降解是一种已知的定数灭策略.
- 细菌物种间的竞争涉及复杂的通信和防御机制.
研究的目的:
- 为了识别超越酶降解的新型定数灭机制.
- 研究IVA型分泌系统 (T4ASS) 效应器在物种间交流中的作用.
- 探索一种新型效应因子LqqE1在阻断AHL合成方面的潜力.
主要方法:
- 鉴定了一种来自Lysobacter酶原OH11.11的T4ASS作用因子 (Le1288).
- 转移了Le1288的位置,变成了Pseudomonas fluorescens 2P24.
- 研究了Le1288和AHL合成酶PcoI之间的相互作用.
- 评估了这种新的"限制人数"机制对生态的影响.
主要成果:
- 称为LqqE1的Le1288通过与AHL合成酶PcoI结合来抑制AHL的产生.
- LqqE1阻断了PcoI对S-adenosy-L-methionine的识别,这是AHL合成的关键基质.
- 这种以效应器为媒介的决数灭为L. enzymogenes OH11.11提供了竞争优势.
- 该机制在其他产生T4ASS的细菌中被观察到,并且具有潜在的应用.
结论:
- 发现了一种涉及T4ASS效应器转移的新型定数灭机制.
- LqqE1代表了一种抑制AHL合成的新类定数灭分子.
- 这一发现突显了效应器介导的物种间沟通的生态意义.
- 在控制人类和植物病原体中,LqqE1具有潜在的应用,例如Pseudomonas aeruginosa和Ralstonia solanacearum.
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