水生环境推动了Listeria中细胞壁缺陷的休眠形式的出现
Filipe Carvalho1, Alexis Carreaux1, Anna Sartori-Rupp2
1INRAE, Université Paris-Saclay, AgroParisTech, Micalis Institute, Jouy-en-Josas, France.
Nature communications
|October 2, 2024
概括
应激的Listeria monocytogenes细菌通过失去细胞壁进入可生存但不可培养 (VBNC) 状态. 这些VBNC细菌可以恢复毒性,构成健康风险.
科学领域:
- 微生物学 微生物学
- 细菌病原体的产生
- 细胞应激反应 细胞应激反应
背景情况:
- 细菌可以在压力下进入可生存但不可培养 (VBNC) 状态,由于不能通过标准方法检测到,这会给健康带来风险.
- 推动过渡到和从VBNC状态的机制尚未完全理解.
- 人类病原体Listeria monocytogenes表现出VBNC行为,需要对其生存策略进行研究.
研究的目的:
- 调查Listeria monocytogenes中VBNC状态转换背后的机制.
- 为了确定关键的调节者和参与VBNC形成和复苏的细胞变化.
- 探索VBNC Listeria可能恢复到毒性状态的可能性.
主要方法:
- 在Listeria monocytogenes中通过在矿泉水中饥饿诱导VBNC状态.
- 微观和生物化学分析以表征细胞形态和稳定性.
- 基因分析以确定关键的细菌应激反应调节剂和酶.
- 使用胚胎进行体内研究,以评估VBNC状态的复苏和毒性.
主要成果:
- 在Listeria monocytogenes中引起饥饿的VBNC状态,其特征是转化为透稳定,缺乏细胞壁的形状.
- 细菌应激反应调节剂SigB和自解素NamA被确定为VBNC状态过渡的关键.
- 在接种到胚胎后,VBNC Listeria成功地恢复到围墙,毒性状态.
- 在水生环境中出现的缺乏细胞壁的细菌形式可能代表一种生存策略.
结论:
- 这项研究阐明了Listeria monocytogenes中VBNC状态过渡的关键分子和形态机制.
- SigB和NamA在Listeria进入和可能退出VBNC状态的能力中起着至关重要的作用.
- 这些发现强调了VBNC Listeria可能构成持续的健康风险,并强调需要新的检测方法.
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