Unraveling the mechanism by which the BAM complex mediates OMP biogenesis

揭示 BAM 复合物介导 OMP 生物发生的机制

基本信息

批准号：
10415950
负责人：
Nicholas Noinaj
金额：
$ 29.63万
依托单位：
PURDUE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-07-08 至 2024-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10415950
关键词：
Affinity Antibiotics Bacteria Binding Biochemical Biogenesis Biological Assay CSPG6 gene Cell Membrane Proteins Cell Survival Cell physiology Communicable Diseases Complex Cryoelectron Microscopy Crystallization Cytoprotection Detergents Development Escherichia coli Genetic Gram-Negative Bacteria Immune response In Vitro Individual Infection Integral Membrane Protein Lateral Libraries Lipid Bilayers Lipoproteins Mediating Membrane Membrane Proteins Methods Micelles Modeling Molecular Molecular Conformation Molecular Machines Multi-Drug Resistance Multiprotein Complexes Mutate Nutrient Pathogenicity Play Process Protein Truncation Proteins Reporting Resolution Roentgen Rays Role Signal Transduction Structure Virulence Virulence Factors Work base biophysical analysis crosslink extracellular in vivo insight interest membrane biogenesis nanodisk pathogenic bacteria protein folding protein function recruit resistant strain structural biology

项目摘要

Project Summary Gram-negative bacteria, such as E. coli, have an outer membrane which provides nutrients and added protection for the cell. The outer membrane also contains proteins that can enable pathogenic bacteria to evade host immune responses and cause a number of serious infectious diseases. Despite the importance of these outer membrane proteins (OMPs) for cell survival and virulence, little is known about how these proteins are folded and inserted into the outer membrane. However, in E. coli, we know that a 200 kDa five-component complex called the β-barrel assembly machinery (BAM) complex mediates the biogenesis of these membrane proteins. In the last decade, the individual structures of components of the BAM complex have been reported with the structure of BamA, the central component, providing the most useful clues to how the BAM complex may function. Here, it was revealed that BamA may destabilize the local membrane, thereby promoting protein folding and insertion into the membrane. Recently, our work and others’ have determined the structure of the BAM complex, revealing unprecedented conformational changes within the barrel domain of BamA. Our work here will utilize these structures to study the role of the conformational changes for the function of the BAM complex in OMP biogenesis. Additionally, we will determine how substrate OMPs are recognized by the BAM complex and how they interact with BAM during folding into the membrane. Lastly, we will use structural biology methods to study the BAM complex in a lipid bilayer and in the presence of substrates. Our proposed studies will provide crucial functional and structural insight towards unraveling how the BAM complex performs its essential role in bacteria.

项目摘要革兰氏阴性细菌，例如大肠杆菌，HABE是一种提供和添加的外膜细胞的保护。尽管您是您的，但寄主的免疫反应并引起许多严重的传染病外膜蛋白（OMP）对于细胞存活和病毒性的重要性，关于但是，这些蛋白质如何折叠并插入外膜。 200 kDa五元组件称为名为β-桶装配机械（BAM）复合物介导您膜蛋白的生物发生。 BAM复合物已与中央组成部分Bama结构相结合，提供了最多 BAM复合物的有用线索可能会在这里起作用。局部膜，从而促进并插入膜和其他人的确定了BAM复合物的结构巴马的桶形领域内的变化。构象会在OPP生物发生中变化BAM复合物的功能确定BAM复合物如何识别底物OMP以及如何与BAM相互作用最后折叠到膜时，我们将使用结构生物学方法来研究BAM 在脂质双层和底物的存在下。结构洞察力揭开BAM复合物如何在细菌中发挥重要作用。