塔马布受PhoPQ的调节,在沙门氏菌病原过程中在外膜恒温中起作用
Rouhallah Ramezanifard1, Yekaterina A Golubeva1, Alexander D Palmer1
1Department of Microbiology, University of Illinois at Urbana Champaign , Urbana, Illinois, USA.
Journal of bacteriology
|September 20, 2023
概括
沙门氏菌通过诱导TamAB系统来补偿应激的外膜蛋白组装复合体来适应巨细胞. 这种PhoPQ调节的系统对于细菌在恶劣的菌体环境中生存至关重要.
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:
- 沙门氏菌在巨细胞中存活,这是一种具有挑战性的环境,通常会消除细菌.
- 该PhoPQ双组件系统调节了沙门氏菌适应菌体的过程,保护其外膜.
- 外膜蛋白组合复合体 (Bam) 对于细菌外膜完整性至关重要.
研究的目的:
- 调查PhoPQ调节的tamAB操作子在巨细胞内的沙门氏菌适应中的作用.
- 为了确定 TamAB 系统和 BAM 复合体之间的功能关系,在法体模拟条件下.
主要方法:
- 在体外和巨细胞中对tamAB操作子转录的分析.
- 对缺乏tamAB或影响Bam功能的沙门氏菌突变的构造和表型分析.
- 在动物模型和巨菌感染中评估细菌存活率和毒性.
主要成果:
- PhoPQ诱导tamAB转录,以应对类似于细胞的条件 (低Mg2+,低pH).
- 在这些条件下,Bam机器受到损害,tamAB删除会加剧Bam突变缺陷.
- 塔马巴补偿了巴姆复杂应激,特别是在模仿巨细胞细胞体的条件下.
结论:
- 由PhoPQ调节的TamAB系统在巨细胞中被诱导,以弥补受损的Bam功能.
- TamAB可能通过调节沙门氏菌生存的外膜特性来间接帮助Bam复合体.
- 这项研究强调了TamAB在维持外膜平衡和沙门氏菌毒性方面的重要性.
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