一个类似PEST的序列在listeriolysin O中对于Listeria monocytogenes的致病性至关重要
1Department of Molecular and Cell Biology, Division of Infectious Diseases, School of Public Health, University of California, Berkeley, CA 94720, USA.
概括
在Listeria monocytogenes listeriolysin O (LLO) 中的一种类似PEST的序列对于病原体的毒性至关重要. 这种序列针对LLO进行降解,防止宿主细胞损伤,并使细胞内生存成为可能.
科学领域:
- 微生物学 微生物学
- 细胞生物学 细胞生物学
- 病原体与宿主之间的相互作用
背景情况:
- 细胞内病原体需要一个受保护的利基生存和复制宿主细胞内.
- 在感染周期期间,Listeria monocytogenes利用孔形成蛋白质listeriolysin O (LLO).
研究的目的:
- 研究一种类似PEST的序列在LLO功能,毒性和细胞内分离中的作用.
- 确定该序列对LLO与宿主细胞相互作用的影响.
主要方法:
- 局部定向突变发生,以产生缺乏类似PEST的序列的LLO突变.
- 细菌进入宿主细胞的分析以及随后的细胞内命运.
- 宿主细胞活力和完整性的评估.
- 类似PEST序列的功能转移到另一个细胞解酶,perfringolysin O.
主要成果:
- 缺乏类似PEST序列的LLO突变进入宿主细胞质中,但导致宿主细胞透和死亡.
- 缺乏PEST类序列的LLO在宿主细胞质中积累,表明它针对LLO进行降解.
- 将类似PEST的序列转移到perfringolysin O使其无毒,并促进细胞内生长.
结论:
- 在LLO中类似PEST的序列对于Listeria monocytogenes的毒性和适当的细胞内分离至关重要.
- 这个序列调解LLO降解,防止过早的宿主细胞溶解,促进病原体的生存.
- 类似PEST的序列可以功能性地转移到其他细胞酶,以调节它们的毒性并促进细胞内生长.
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