测量活菌体中的膜流动性揭示了亚细胞侧向变异和对菌膜扰动的极选择性反应
bioRxiv : the preprint server for biology
|September 18, 2025
概括
在活细胞中直接测量了对抗生素耐受性至关重要的mycobacterial细胞外流动性. 这揭示了空间变异,并将流动性变化与抗生素易感性联系起来,为细菌生存策略提供了新的见解.
科学领域:
- 微生物学 微生物学
- 生物物理学的生物物理.
- 细胞生物学 细胞生物学
背景情况:
- 菌根细菌细胞外是抗生素耐受性和抗压力的关键.
- 现有模型表明,低膜流动性阻碍了抗生素的进入,但在活细胞中直接测量很少.
- 膜流动性是动态调节的,对整个生命的细胞过程至关重要.
研究的目的:
- 开发和验证一种方法来测量活菌体细胞外流动性.
- 为了研究细胞下局部化,抗生素治疗和遗传因素如何影响菌根菌膜流动性.
- 探索细胞外生物物理性质和抗生素敏感性之间的关系.
主要方法:
- 利用C-Laurdan探头进行基于成像和流细胞计的测试.
- 将该方法应用于各种真菌细菌物种,包括 *M. smegmatis* 和 *M. tuberculosis*.
- 分析了基于亚细胞位置,抗生素暴露和遗传突变的流动性变化.
主要成果:
- 观察到明显的流动性模式:极点比侧墙更流动,旧极点比新极点更流动.
- 在分化后的子细胞中表现出不平等的膜流动性,在特定的突变体中减少了不对称性.
- 发现菌膜破坏改变了流动性,增加了对抗生素的敏感性.
结论:
- 在真菌细菌中,直接测量活细胞外流动性是可行的.
- 细胞膜流动性表现出与生长和分裂相关的空间和时间异质性.
- 菌膜流动性模式与抗生素敏感性相关,这表明预测生物标志物的潜力.
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