相关实验视频
Updated: Jan 10, 2026

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An In Vitro Assay to Detect tRNA-Isopentenyl Transferase Activity
Published on: October 8, 2018
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一种类似于HipA的毒素的中和机制,向Isoleucyl-tRNA合成酶
Si-Ping Zhang1, Ying-Jie Song2, Yi-Ping Ye3
1Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China; Central Laboratory, Nanyang Central Hospital, Nanyang 473000, China.
Journal of molecular biology
|November 26, 2025
概括
这是一种HipB抗毒素.
科学领域:
- 细菌毒素-抗毒素系统
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 毒素-抗毒素 (TA) 系统调节细菌的生长和生存.
- HipBA系统是一种II型TA系统,含有HipA毒素和HipB抗毒素.
- 像HipBA这样的系统的结构和功能多样性尚未得到充分理解.
研究的目的:
- 调查来自Pseudomonas fluorescens (HipBAPf) 的类似HipBA的模块.
- 阐明HipBPfC终端区域在HipAPf中和中的结构和功能作用.
- 确定HipAPf的特定分子标.
主要方法:
- 在X射线晶体学.
- 在AlphaFold建模中使用AlphaFold模型.
- 变异发生的测试.
主要成果:
- HipBPf C端区域在结合HipAPf时形成两个α螺旋,这对于中和至关重要.
- HipBPf结合通过阻断ATP结合部位来抑制HipAPf,可能是通过结构变化.
- 在Ser604中,HipAPf可化异基-tRNA合成酶,抑制其氨基化活性.
结论:
- HipBPfC端区域对于毒素结合和中和至关重要.
- 与其他HipA毒素相比,HipAPf具有不同的基质特异性.
- 了解HipBAPf提供了对TA系统多样性和细菌生长调节的见解.
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