在I型毒素-抗毒素系统中存在的缺陷可能会导致压力诱导的持续形成
Sofija Markovic1, Magdalena Djordjevic2,3, Hong-Yu Ou4
1Quantitative Biology Group, Faculty of Biology, University of Belgrade, Studentski trg 16, Belgrade, Serbia.
NPJ systems biology and applications
|December 22, 2025
概括
细菌抗生素持久性,导致慢性感染的细胞,使用I型毒素-抗毒素 (TA) 系统进行建模. 这些系统表现出双稳定性,在正常生长和持久状态之间切换,特别是在压力下.
科学领域:
- 微生物学和分子生物学
- 系统生物学 系统生物学
- 理论生物学 理论生物学
背景情况:
- 抗生素持久性是一种休眠的细菌亚群,对持久性和复发性感染负责.
- 形成持久性背后的机制尚未完全理解,尽管已知数十年.
- 毒素-抗毒素 (TA) 系统与细菌的生存有关,并且是持久细胞的潜在调节者.
研究的目的:
- 开发一种由I型毒素-抗毒素 (TA) 系统驱动的持久性形成的第一个理论模型.
- 研究在各种条件下,包括压力下,持续形成的动态.
- 阐明TA系统中反机制对于调节细菌持久性的作用.
主要方法:
- 为I型TA系统开发理论模型,其中抗毒素是小RNA.
- 数学分析和计算模拟以探索系统动态和稳定状态.
- 导出稳定性图和使用顶点灾难表面来分析系统属性.
主要成果:
- 该模型展示了两个稳定的状态:低毒素 (正常生长) 和高毒素 (持久性),随着随机切换.
- 对于持久性至关重要的双性通过反循环保持,涉及抑制抗毒素降解.
- I型TA系统可以通过进入可视化状态来诱导在压力下 (例如,抗生素,营养限制) 的持续性.
结论:
- I型TA系统提供了持续细胞形成的机制基础,特别是在压力条件下.
- 该模型解释了短暂缓慢生长的细胞如何稳定,而长寿细胞如何持续.
- 该框架提供了对抗生素耐药性的见解,并建议治疗策略的潜在目标.
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