Bacterial Outer Membranes and Interactions with Proteins

细菌外膜及其与蛋白质的相互作用

• 批准号: 1516154
• 负责人: Wonpil Im
• 金额: $ 42.5万
• 依托单位: University of Kansas Center for Research Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-15 至 2017-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1516154&HistoricalAwards=false
• 关键词: Bacterial; Outer; Membranes; Interactions; Proteins

The cytoplasm of gram-negative bacteria is surrounded by a membrane composed of two layers: the inner membrane (or periplast) and the outer membrane (OM). The OM separates the periplasm from the external environment and functions as a selective barrier that prevents the entry of toxic molecules such as antibiotics and bile salts into the bacteria. This selective barrier is crucial for survival of bacteria in diverse and hostile environments. This project seeks to acquire an in-depth and molecular-level understanding of how the bacterial OMs behave and work for various types of bacteria, how membrane proteins behave in the OM and interact with the OM, and how solute molecules, especially antibiotics, can enter through the OMs. This will be accomplished using start-of-the-art molecular modeling and simulations. This project will also form the basis for a general approach for molecular modeling and simulation of the OM that will be freely available through the CHARMM-GUI website (www.charmm-gui.org) so that researchers in various disciplines can investigate other important OMs and associated proteins. Both graduate and undergraduate students will be trained in the interdisciplinary discipline of computational biophysics. In particular, this project will raise the scientific literacy of the public through the publication of research results and workshop participation.The cell envelope surrounding a gram-negative bacteria's cytoplasm is composed of an inner membrane, the periplasm, and an outer membrane (OM). The OM is unique in terms of having beta-barrel membrane proteins and a highly asymmetric lipid bilayer containing phospholipids in its inner leaflet and lipopolysaccharide (LPS) in its outer leaflet. This project aims to provide an in-depth and unprecedented understanding of the structural and dynamics of the OMs from various bacteria, interactions between proteins and OMs, and their influences on antibiotic permeation by establishing reliable computational methods for all-atom modeling and simulation of various complex OMs of gram-negative bacteria and membrane proteins in various OMs. The research will found the basis for a general approach of LPS/OM molecular modeling and simulation. This project also seeks to foster synergistic scientific research and education on LPS molecules and bacterial OMs by providing reliable and general computational methods (through LPS Modeler and Outer Membrane Builder in CHARMM-GUI) to students and researchers in the simulation community and other disciplines.

革兰氏阴性菌的细胞质被由两层组成的膜包围：内膜（或周质）和外膜（OM）。 OM将周质与外部环境分离，并作为一种选择性屏障，防止抗生素和胆盐等有毒分子进入细菌。 这种选择性屏障对于细菌在多样化和恶劣环境中的生存至关重要。该项目旨在深入和分子水平的了解细菌OM如何表现和为各种类型的细菌工作，膜蛋白如何在OM中表现并与OM相互作用，以及溶质分子，特别是抗生素，如何通过OM进入。 这将使用最先进的分子建模和模拟来完成。该项目还将形成OM分子建模和模拟的一般方法的基础，该方法将通过CHARMM-GUI网站（www.charmm-gui.org）免费提供，以便各学科的研究人员可以研究其他重要的OM和相关蛋白质。研究生和本科生都将接受计算生物物理学跨学科的培训。特别是通过发表研究成果和参加研讨会，提高公众的科学素养。革兰氏阴性菌的细胞质被膜由内膜、周质和外膜（OM）构成。OM的独特之处在于具有β-桶膜蛋白和高度不对称的脂质双层，其内小叶中含有磷脂，其外小叶中含有脂多糖（LPS）。该项目旨在通过建立可靠的计算方法，对革兰氏阴性菌的各种复杂有机分子和各种有机分子中的膜蛋白进行全原子建模和模拟，从而深入和前所未有地了解各种细菌的有机分子的结构和动力学，蛋白质和有机分子之间的相互作用及其对抗生素渗透的影响。该研究为LPS/OM分子模拟的通用方法奠定了基础。该项目还旨在通过向模拟社区和其他学科的学生和研究人员提供可靠和通用的计算方法（通过CHARMM-GUI中的LPS Modeler和Outer Membrane Builder），促进LPS分子和细菌OM的协同科学研究和教育。