SlyB 在压力诱导的脂质纳米域中封装了外膜蛋白
Arne Janssens1,2, Van Son Nguyen1,2, Adam J Cecil3
1Structural and Molecular Microbiology, VIB-VUB Center for Structural Biology, VIB, Brussels, Belgium.
Nature
|December 11, 2023
概括
SlyB是一种细菌脂蛋白,在压力时形成保护复合体. 这些复合物通过稳定蛋白质和脂质来维持外膜的完整性,这对细菌的生存至关重要.
科学领域:
- 微生物学
- 细胞生物学
- 生物化学
背景情况:
- 格拉姆阴性细菌具有独特的外膜,由脂和脂多糖组成,对细胞完整性至关重要.
- 这种膜密集地含有外膜蛋白 (OMP) 和脂蛋白,需要精确调节.
- 保持外膜的结构完整性对于细菌的生存和功能至关重要.
研究的目的:
- 研究SlyB脂蛋白在压力条件下维持细菌外膜完整性的作用.
- 阐明SlyB与外膜蛋白质和脂质双层相互作用的结构机制.
- 了解SlyB在应对抗菌和阳离子短缺等环境挑战中的功能.
主要方法:
- SlyB结构的特征,包括其周等离子域和跨膜螺旋.
- 在脂质不对称性丧失后,对SlyB寡合化成环形复合物的分析.
- 研究SlyB在封装外膜蛋白 (OMP) 成为脂质纳米域中的作用.
- 在存在或不存在SlyB的压力条件下评估细菌生存和外膜功能.
主要成果:
- SlyB与外膜蛋白质组形成稳定的压力诱导的复合体.
- SlyB 聚合成类似环状的结构,形成脂质纳米域,封装 OMP.
- 这些SlyB形成的纳米域在抗菌或阴离体缺乏期间保持外膜完整性至关重要.
- 在压力下,SlyB功能丧失导致外部膜屏障功能受损和OMPs丧失.
结论:
- SlyB 作为一个隔离性跨膜保护蛋白,对细胞包膜蛋白质稳定和格兰阴性细菌的完整性至关重要.
- SlyB形成脂质纳米域的能力是压力时保护外膜的关键机制.
- 这些发现表明SlyB代表了一种保存的脂蛋白家族,在细菌应激反应和生存中起着重要作用.
相关概念视频
Membrane Domains
5.4K
The membrane domains concentrate specific lipids and proteins at one place within the membrane, which helps in cell signaling, adhesion, and other critical cellular processes. These domains can differ in size, composition, function, and lifespan.
Protein Domains
The membrane comprises a group of distinct proteins responsible for carrying out a cell's specific function. For example, the plasma membrane of the human sperm, or a single germ cell, contains a unique set of proteins in the...
Protein Domains
The membrane comprises a group of distinct proteins responsible for carrying out a cell's specific function. For example, the plasma membrane of the human sperm, or a single germ cell, contains a unique set of proteins in the...
5.4K
Mechanisms of Membrane Domain Formation
3.0K
Different physical properties of lipids and proteins allow them to localize and form distinct islands or domains in the membrane. Some membrane domains are formed due to protein-protein interactions, whereas others are formed due to the presence of specific lipids such as sphingolipids and sterols—for example, large proteins, such as bacteriorhodopsin, aggregate and create distinct domains.
Another mechanism for membrane domain formation involves membrane proteins interacting with...
Another mechanism for membrane domain formation involves membrane proteins interacting with...
3.0K
Assembly of the Lipid Bilayer in the ER
3.2K
Biological membranes are more than just a barrier separating cell cytoplasm from the outside environment. They are highly dynamic and help maintain the integrity and physiological stability of the cells as well as membrane-bound organelles. Membranes also play vital roles in cell-to-cell and intracellular communication.
A large chunk of any biological membrane is composed of phospholipids. These lipids have a heterogeneous distribution across different subcellular organelles and even between...
A large chunk of any biological membrane is composed of phospholipids. These lipids have a heterogeneous distribution across different subcellular organelles and even between...
3.2K
Asymmetric Lipid Bilayer
7.3K
Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...
7.3K
Regulation of Nuclear Protein Sorting
2.4K
Nuclear protein sorting regulates nucleus composition and gene expression, crucial for determining the fate of a eukaryotic cell. Hence, the entry and exit of molecules across the nuclear envelope is a tightly controlled process. Nuclear protein sorting can be inhibited by one of the following ways: 1) masking cargo signal sequences, 2) modifying the nuclear receptor's affinity for cargo, 3) controlling the nuclear pore size, 4) retaining the cargo during its transit to the cytosol or the...
2.4K
Clathrin Coated Vesicles
7.0K
Clathrin-coated vesicles use endocytosis to transport receptors and lysosomal hydrolases from the Golgi to the lysosome in the late secretory pathway. Clathrin-mediated endocytosis was the first described endocytic process, and Clathrin-coated vesicles remain one of the most well-studied transport vesicles. The molecular machinery that generates clathrin-coated vesicles comprises over 50 proteins that precisely coordinate vesicle formation. Cell surface receptors concentrated in indented sites...
7.0K


