通过Mycobacterium结核病MazF毒素对16SrRNA抗Shine-Dalgarno序列的有针对性的去除
Timothy W Sherrier1, Valdir C Barth1, Jason M Schifano1
1Department of Biochemistry and Molecular Biology, Rutgers University, Robert Wood Johnson Medical School, Piscataway, New Jersey, USA.
The Journal of biological chemistry
|June 1, 2025
概括
结核病原体 Mycobacterium tuberculosis 具有第 11 种 MazEF 毒素,即 MazF-mt11. 这种毒素向16S核糖体RNA,抑制蛋白质合成,并可能有助于细菌的持久性.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 结核病原体Mycobacterium tuberculosis (Mtb) 拥有众多的II型毒素-抗毒素 (TA) 系统,假设有助于对抗生素和宿主免疫的生存.
- 虽然Mtb拥有约70个TA系统,其中包括10个MazEF家族成员,但大多数MazF毒素的具体目标仍然未知.
研究的目的:
- 为了识别和表征Mtb中的第11个MazEF毒素对应物,命名为MazF-mt11.
- 为了确定MazF-mt11.11的特定RNA标和裂解部位.
- 为了阐明MazF-mt11在Mtb中的功能性作用.
主要方法:
- 再组合的MazF-mt11被用于切割MS2细菌RNA,随后进行了原料扩展以确定切割部位.
- 通过过度表达RNase在大肠杆菌的Escherichia coli映射 (MORE) RNA测序被用于定义MazF-mt11裂变共识序列.
- 5'-OH RNA测序被用来识别MazF-mt11在Mtb.中的细胞RNA标.
主要成果:
- 在Mtb.中,MazF-mt11被确定为第11个MazEF毒素对应物.
- 该毒素在C↓A位点分裂RNA,共识序列为C↓ACCU.
- 发现MazF-mt11仅针对Mtb中的16S核糖体RNA (rRNA),在抗Shine-Dalgarno序列之前分裂它.
- 这种在16S rRNA的抗Shine-Dalgarno序列附近的裂变显著抑制了蛋白质合成.
结论:
- MazF-mt11是一种特定于序列的内啡核糖酶,准16SrRNA,对核糖体功能至关重要.
- 由MazF-mt11抑制蛋白质合成表明它在Mtb.的非复制性持久状态中的作用.
- 了解MazF-mt11的功能,可以了解Mtb的生存机制和潜在的治疗点.
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