循环二-AMP抑制了Listeria monocytogenes在感染期间的无甲状腺死亡
Joshua P Leeming1, Omar M Elkassih1, Damilola T Oyebode1
1Department of Biology, University of Texas at Arlington, Arlington, Texas, USA.
mBio
|December 11, 2025
概括
循环二-AMP (c-di-AMP) 调节了Listeria monocytogenes中的无甲状腺死亡 (TLD). 降低c-di-AMP水平增加了细菌细胞死亡,减少了感染,为菌病揭示了新的治疗点.
科学领域:
- 微生物学 微生物学
- 细菌病原体的产生
- 药物发现 药物发现 药物发现
背景情况:
- 抗叶酸抗生素通过抑制胆固醇合成酶 (ThyA),诱导无胆固醇死亡 (TLD) 来对抗耐药的李斯特菌单细胞菌 (Lm).
- 感染期间TLD的机制尚不清楚,这阻碍了有效的菌病治疗.
- 循环二AMP (c-di-AMP),一种细菌的第二信使,被抗叶酸提升,但其在TLD中的作用尚不清楚.
研究的目的:
- 阐明c-di-AMP在感染期间Lm中调节TLD中的作用.
- 调查c-di-AMP调节对Lm存活率和毒性的影响.
- 通过了解TLD监管来确定菌病的潜在治疗点.
主要方法:
- 利用一种提米丁辅助性Lm突变体 (ΔthyA) 在体外和体内研究TLD.
- 操纵c-di-AMP水平和评估细菌细胞死亡,细胞内生长和感染模型 (口服和静脉注射).
- 研究了c-di-AMP结合蛋白PstA对细菌细胞死亡的贡献.
主要成果:
- 需要高的c-di-AMP来抑制Lm中的TLD;降低c-di-AMP会增加胺素饥饿下的细胞死亡.
- 在口腔感染中,dThyA突变体表现出更大的生长缺陷,这是由于蒂米丁的可用性有限.
- 降低c-di-AMP取消了ΔthyA突变的感染能力;当c-di-AMP低时,PstA删除挽救了细胞死亡.
结论:
- 发现了一种新的c-di-AMP介导的机制来调节Lm中的TLD.
- 证明c-di-AMP水平对于感染期间的Lm生存和毒性至关重要.
- 建议结合治疗策略,以抗叶酸和c-di-AMP代谢为菌病治疗的目标.
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