在本地条件下,大肠杆菌从大肠杆菌释放的胆素E9的动态
Shaista Bano1,2, Sarfraz Ali Tunio2, Christopher N Penfold1
1School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
Letters in applied microbiology
|April 23, 2024
概括
大肠杆菌中的本地pColE9-J等离子体,尽管有两个溶解基因,但并没有导致细胞快速死亡. 相反,一些细胞表现出外膜损伤,这表明混合种群的生存优势.
科学领域:
- 微生物学 微生物学
- 细菌学 细菌学是一门学科.
- 分子生物学分子生物学
背景情况:
- 素等离子体对素蛋白进行编码,通过SOS可诱导促进体调节的宿主细胞溶解释放出来.
- 氨酸等离子体上的溶解基因对于氨酸出口和生产细胞死亡至关重要,影响培养度.
研究的目的:
- 在诱导条件下,研究含有本地pColE9-J等离子体的大肠杆菌在种群水平的细胞死亡和溶解动态.
- 为了确定两个溶解基因的扩展ColE9操作子是否会影响细胞溶解和素释放异质性.
主要方法:
- 使用了米托米辛C敏感性试验来诱导基因表达.
- 用于定量细胞死亡检测的活/死染色.
- 与本地pColE9-J和单个溶解基因删除突变体 (∆celE, ∆celI) 之间的溶解表型进行了比较.
主要成果:
- 本地pColE9-J等离子体在诱导线粒素C时没有诱导培养度的快速下降.
- 大肠杆菌细胞的一个子集表现出外膜扰动,这种表型在单 lysis 突变中没有见到.
- 观察到素E9释放和差异外膜穿孔的异质性表明细胞反应各异.
结论:
- 在原生pColE9-J等离子体上扩展的ColE9操作子导致异质细胞溶解和胆释放.
- 不同外膜损伤可能会给混合种群中的生产细胞带来竞争优势.
- 这种异质性挑战了在素操作子诱导后细胞死亡均的假设.
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