MenT核酸转移酶毒素扩展tRNA受体茎,可以通过不对称的抗毒素结合抑制
Xibing Xu1, Ben Usher2, Claude Gutierrez3
1Laboratoire de Microbiologie et Génétique Moléculaires (LMGM), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, Université Toulouse III - Paul Sabatier (UT3), Toulouse, France.
Nature communications
|August 17, 2023
概括
结核菌毒素-抗毒素系统对于细菌的生存至关重要. 这项研究揭示了MenAT1毒素-抗毒素系统如何修改tRNA,MenA1抗毒素阻断MenT1活动.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 结核菌菌具有许多具有未知的功能的毒素-抗毒素系统.
- 核基转移酶毒素-抗毒素系统的MenAT家族广泛存在.
- 之前的工作在M.结核病中确定了四个MenAT系统.
研究的目的:
- 为了描述来自M.结核病的MenAT1毒素-抗毒素系统.
- 阐明MenT1tRNA修饰和MenA1抗毒素抑制的机制.
- 为了调查MenT家族内的保存活动.
主要方法:
- tRNA测序以检测MenT1修饰活动.
- 生物化学试验研究MenT1-MenA1相互作用.
- 进行X射线晶体学以确定复杂的结构.
主要成果:
- 证实MenT1具有tRNA修饰活性.
- MenA1抗毒素通过与MenT1折叠结合来抑制MenT1的活性.
- 一个异构的MenAT1复杂结构揭示了不对称的MenA1结合.
- MenT4毒素也表现出tRNA修饰活性,表明功能得到保护.
结论:
- MenAT1是一种功能性毒素-抗毒素系统,参与tRNA修饰.
- MenA1采用一种独特的抑制机制,与其他抗毒素不同.
- MenT家族显示保存的tRNA修饰,但有不同的点特异性和抗毒素相互作用.
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