前切除激活了利斯特菌能力基因,这些基因促进了体逃逸和毒性
Lev Rabinovich1, Nadejda Sigal, Ilya Borovok
1Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Tel Aviv 69978, Israel.
Cell
|August 21, 2012
概括
以前被认为是非功能性的Listeria monocytogenes能力 (Com) 系统,对于细菌在感染期间从宿主细胞逃离至关重要. 孕细胞作为基因开关,使通讯系统能够在没有DNA转换的情况下运行.
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:
- 在*Listeria monocytogenes*中的能力 (Com) 系统被广泛认为是非功能性的,主要调节基因 (comK) 由于prophage而被破坏.
- 在这种病原体中没有发现DNA转换的条件.
研究的目的:
- 为了研究在宿主感染期间Listeria monocytogenes* Com系统的作用.
- 阐明了涉及prophage和comK基因的调节机制.
主要方法:
- 在细胞内细菌生长过程中对Com系统的功能进行分析.
- 探究预兆细胞切除及其对comK基因完整性的影响.
- 评估细菌从巨细胞的虫体中逃逸.
主要成果:
- 对于Listeria monocytogenes来说,Com系统是必不可少的,因为它可以在感染期间逃离巨细胞的虫体,而不依赖于DNA吸收.
- 在细胞内生长过程中诱导的食原体切除可以恢复功能性的comK基因.
- 前切除发生在没有产生传染性病毒颗粒的情况下,作为特定的遗传开关.
结论:
- *Listeria monocytogenes* Com系统是一个活跃的毒性因子,不参与DNA转化.
- 温和的prophage作为条件遗传开关,通过控制comK基因表达来调节感染期间的细菌毒性.
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