通过单粒子冷-EMEM揭示的细菌植物色素中的摄影感应和信号传递
Tek Narsingh Malla1, Carolina Hernandez2, Srinivasan Muniyappan1
1Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA.
Science advances
|August 9, 2024
概括
细菌的植物染色体充当光传感器,在状态之间切换,以控制胺激酶 (HK) 活动. 新的冷EM结构揭示了一种异构体中间体,解释了这些光受体中的光信号转导.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 微生物学 微生物学
背景情况:
- 植物染色体是植物,细菌和真菌中发现的感光蛋白.
- 它们通过Pr和Pfr状态之间的可逆光循环来调节生理反应.
- 光引起的变化控制着一个相关的酶域,通常是一个histidine kinase (HK).
研究的目的:
- 阐明光线控制细菌植物染色体中胺激酶活性的分子机制.
- 为细菌植物染色体的信号状态提供结构性见解.
- 了解植物染色体在细菌双组分光信号系统中的作用.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定高分辨率结构.
- 获得了Pr和Pfr同极体的结构,以及一个Pr/Pfr异极体.
- 分析的重点是野生类型的细菌植物染色体,具有内在的HK活性.
主要成果:
- 确定了细菌植物染色体的三个不同的冷EM结构.
- 结构捕获了Pr-Pr,Pfr-Pfr同极体和一个独特的Pr-Pfr异极体.
- 建议Pr/Pfr异构体作为信号传导中的关键中间体.
结论:
- 这项研究为细菌植物染色体中的Pr/Pfr异构体中间体提供了第一个结构证据.
- 这种异构体结构为光调节的HK活性提供了分子解释.
- 这些发现揭示了细菌双组分系统中光感知和信号传导的机制.
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