在营养应激下,黄金葡萄球菌主要病原体扩张的临床rel突变
Edwin Chen1, Marla G Shaffer1, Robert E Bilodeau1
1Division of Infectious Diseases, Department of Medicine, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania, USA.
mSphere
|September 26, 2023
概括
在营养不良的条件下,五种Staphylococcus aureus相关突变增强了细菌的严格反应 (SR),有助于对宿主免疫力的生存. 这些突变使细菌在枯竭的环境中生长,这是持续感染的关键生存策略.
科学领域:
- 微生物学 微生物学
- 细菌病原体的产生
- 分子生物学分子生物学
背景情况:
- 持续的金黄色葡萄球菌感染与严格反应 (SR) 有关,由Rel蛋白调节.
- 瑞尔合成了 (p) pGpp 警报,通过调节生长和毒性,使细菌能够适应压力.
- 在之前,在患有持续性甲素耐药性黄金色杆菌菌病的患者中,在rel中发现了五种新的蛋白质改变突变.
研究的目的:
- 在体内表征5种新型转基因突变的体内表型在金黄色葡萄球菌.
- 了解这些突变在持续感染期间是如何被选择的.
- 在营养有限的环境中研究rel突变,严格响应激活和细菌适应性之间的联系.
主要方法:
- 引入5个已识别的相关突变到金黄色葡萄球菌菌株JE2.2.
- 分析细菌生长,健康状况和抗生素耐药性概况.
- 量化细胞内 (p) pGpp水平以评估严格反应激活.
主要成果:
- 所有五种相关突变都汇聚到一个单一的表型中,缩短了滞后期生长,并在营养不足的情况下增加了健康.
- 这些突变与在增长的静止阶段加强严格反应激活有关.
- 与之前发现的临床相关突变不同,这些突变没有产生抗生素耐受性.
结论:
- 鉴定到的相关突变增强了严格的响应信号,特别是在营养不良的环境中.
- 这种增强的SR使金黄色葡萄球菌在营养压力下生长和生存,可能有助于逃避宿主营养免疫力.
- 这些发现揭示了细菌在持续感染期间逃避宿主强加的营养免疫力的战略.
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