小蛋白MntS从一个信号进化而来,并获得了一种新功能,调节大肠杆菌中的恒常性
Zachary Wright1, Mackenzie Seymour1, Kalista Paszczak1
1Department of Chemistry, University of Wisconsin, Oshkosh, Wisconsin, USA.
Molecular microbiology
|December 17, 2023
概括
像MntS这样的小蛋白质通过抑制MntP载体来调节 (Mn) 运输. 由Mn触发的MntS自我组装提供了下调机制,揭示了其与信号的进化联系.
科学领域:
- 分子生物学和生物化学 分子生物学和生物化学
- 细菌生理学和恒常状态.
- 蛋白质与蛋白质的相互作用和调节
背景情况:
- 小型蛋白质 (<50个氨基酸) 是各种生物的关键调节者,在压力期间经常调节较大的蛋白质功能.
- 关于小蛋白机制,下调和进化起源的基本知识仍然有限.
- (Mn) 对于细菌的生存至关重要,但在高度下是有毒的,需要严格控制平衡.
研究的目的:
- 为了阐明MntS小蛋白在平衡中的调节机制.
- 为了研究MntS和MntP运输体之间的相互作用.
- 探索MntS与同源信号的进化来源和功能关系.
主要方法:
- 生物化学试验以表征MntS-MntP相互作用.
- 在的存在下对MntS自组装的分析.
- 对MntS与同源信号和基因社区进行比较分析.
主要成果:
- 小型MntS蛋白直接结合并抑制MntP运输体,为Mn稳态增加了一种新的调节层.
- MntS经历了依赖Mn的自我组装,这表明了终止MntP抑制的机制.
- 在功能上,MntS对Mn进口物SitA的信号具有同类性,保留区域替代MntS功能.
结论:
- MntS代表了运输的独特监管机制,与转录和转录后控制不同.
- MntS的自我组装提供了一个潜在的反循环,用于调节其抑制活性.
- MntS很可能是从一个祖先的SitA蛋白的信号进化而来的,在平衡中获得了专门的作用.
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