两种防御系统消除了第七次大流行病毒的等离子体
Milena Jaskólska1, David W Adams2, Melanie Blokesch3
1Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, Station 19, EPFL-SV-UPBLO, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
Nature
|April 7, 2022
概括
在流行性Vibrio cholerae菌株中发现了两种新的等离子体防御系统DdmABC和DdmDE. 这些系统消除了等离子体,并对菌体进行防御,影响了细菌的进化和抗生素耐药性的传播.
科学领域:
- 细菌遗传学和进化
- 微生物致病
- 移动的遗传元素
背景情况:
- 横向基因转移 (HGT) 通过等离子体和细菌体等移动遗传元素驱动细菌的适应.
- 细菌拥有针对侵入性移动遗传元素的多种防御机制.
- 致使第七次霍乱大流行的Vibrio cholerae El Tor菌株具有独特的遗传特征.
研究的目的:
- 鉴定和描述大流行性Vibrio cholerae中的等离子体防御系统.
- 调查这些防御系统的机制和目标.
- 了解这些系统在塑造大流行性V.霍乱和抗生素耐药性的传播中的作用.
主要方法:
- 对Vibrio cholerae El Tor菌株进行基因分析.
- 塑体和菌体挑战测试
- 对防御系统DdmABC和DdmDE的行动研究机制.
- 对携带等离子体的细胞进行体能测试.
主要成果:
- 在流行性V.霍乱中发现了两个保存的等离子体防御系统DdmABC和DdmDE.
- 这些系统合作降解小的多副本质粒.
- DdmABC通过流产性感染 (Abi) 提供对细菌菌体的防御,并对携带大等离子体的细胞 (包括IncC多药性等离子体) 施加适应性成本.
- 在流行性V.霍乱菌株中,等离子体很少见,与它们在环境菌株中的丰富性形成鲜明对比.
结论:
- DdmABC和DdmDE系统是控制等离子体携带的流行V.霍乱的关键因素.
- 这些发现解释了流行病菌株中等离子体的低患病率,并对了解抗生素耐药性等离子体的传播有影响.
- 这些防御系统的相互作用, 塑造了流行性霍乱病毒的成功.
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