一个非常通用的分子机器
1Department of Biology, Texas A&M University, College Station, Texas, USA.
Journal of bacteriology
|September 30, 2024
概括
研究人员通过结合细菌鞭毛状态器和系统组件,创建了混合离子驱动电机. 只有一个混合体支持大肠杆菌的运动性,这表明这些基本细胞机器的共同祖先和功能分歧.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 细菌鞭毛电机和系统的ExbBD复合体是离子驱动的运输系统,对分别运动性和营养吸收至关重要.
- 这些系统具有结构上的相似性,这表明了潜在的进化关系.
- 了解这些电机之间的功能相互作用,可以了解它们的进化分歧.
研究的目的:
- 为了研究细菌鞭毛状态器单元和系统的ExbBD复合体之间的功能兼容性和进化关系.
- 通过结合两种系统的组件来构建和描述仿真离子驱动电机.
- 为了确定这些不同但相关的分子机器的功能中涉及的关键区域和残留物.
主要方法:
- 通过将细菌鞭毛的定位器单元与ExbBD组件合并,构建14个模拟离子驱动电机.
- 通过测试大肠杆菌的游泳运动性来评估嵌合体运动功能.
- 局部定向突变发生,在有前途的杂交结构中引入额外的残留变化,以增强运动性.
主要成果:
- 在14个构造的杂交物中,只有一个在大肠杆菌中表现出功能性游泳运动性.
- 在非杂交区域的三个额外的残留物变化显著提高了功能杂交的运动性.
- 在创建功能混合体方面取得的有限成功表明了特定的结构和功能约束.
结论:
- 细菌鞭毛状态器单元和ExbBD共享一个共同的进化祖先.
- 尽管存在差异,但保留区域允许有限的功能补充,表明共享的祖先机器.
- 这项研究提供了离子驱动运动系统的进化可塑性及其适应不同细胞作用的证据.
相关概念视频
Microtubule Associated Motor Proteins
7.7K
Eukaryotic cells have different motor proteins for transporting various cargo within the cell. These motor proteins differ based on the filament they associate with, the direction they move within the cell, and the type of cargo they transport. Motor proteins that associate with microtubules are known as microtubule-associated motor proteins. There are two families of microtubule-associated motor proteins —Kinesins and Dyneins. Both these proteins assist in the transport of cellular...
7.7K
Mechanical Protein Functions
4.9K
Proteins perform many mechanical functions in a cell. These proteins can be classified into two general categories- proteins that generate mechanical forces and proteins that are subjected to mechanical forces. Proteins providing mechanical support to the structure of the cell, such as keratin, are subjected to mechanical force, whereas proteins involved in cell movement and transport of molecules across cell membranes, such as an ion pump, are examples of generating mechanical force.
4.9K
Mechanical Protein Function
2.0K
2.0K
Protein Complexes with Interchangeable Parts
2.5K
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order...
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order...
2.5K
ATP Driven Pumps III: V-type Pumps
3.6K
V-type pumps are ATP-driven pumps found in the vacuolar membranes of plants, yeast, endosomal and lysosomal membranes of animal cells, plasma membranes of a few specialized eukaryotic cells, and some prokaryotes. They are also known as the V1Vo-ATPase, that couple ATP hydrolysis to transport protons against a concentration gradient.
The peripheral or cytosolic V1 domain with eight subunits is involved in ATP hydrolysis. The integral or transmembrane V0 domain containing at least five subunits...
The peripheral or cytosolic V1 domain with eight subunits is involved in ATP hydrolysis. The integral or transmembrane V0 domain containing at least five subunits...
3.6K
ATP Synthase: Structure
11.9K
ATP synthase or ATPase is among the most conserved proteins found in bacteria, mammals, and plants. This enzyme can catalyze a forward reaction in response to the electrochemical gradient, producing ATP from ADP and inorganic phosphate. ATP synthase can also work in a reverse direction by hydrolyzing ATP and generating an electrochemical gradient. Different forms of ATP synthases have evolved special features to meet the specific demands of the cell. Based on their specific feature, ATP...
11.9K


