MECHANISM OF ION TRANSPORT THROUGH MEMBRANE CHANNELS

离子通过膜通道的传输机制

• 批准号: 3286976
• 负责人: Roger E Koeppe
• 金额: $ 9.24万
• 依托单位: UNIVERSITY OF ARKANSAS AT FAYETTEVILLE
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-09-01 至 1992-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3286976
• 关键词: X ray crystallography; bacterial proteins; chemical structure function; colicines; dimer; dipole moment; electrical conductance; gramicidin; ion transport; membrane channels; membrane permeability; membrane potentials; membrane proteins; neutron diffraction; physical separation; stereochemistry

The chemistry of ion transport at the molecular level is understood only in quite general terms. The aim of this research is to enhance the understanding of rapid and selective ion transport through transmembrane channels at the molecular level. The gramicidin family of channels is a powerful system for investigating the interactions among ion, protein and lipid during the transport process. The gramicidin family represents a related series of peptides of known structure, in which specific changes in structure and the specific placement of polarizable substituents can be correlated with channel selectivity, stability, lipid dependence and transport properties. Advantages of the gramicidin family include: ideal selectivity for monovalent cations, partial intercationic specificity, single-file characteristics, its generally accepted structure, the availability of natural and synthetic analogues, and a sensitive assay for the equivalence of native and analogue conformations. This research will address the chemical control of the elementary steps of transport using both kinetic and equilibrium techniques. Site- specific modifications of the gramicidin channel will be used to (i) investigate channel properties and structure-function relationships, and (ii) design new molecular features that extend the function of the parent molecule. The results are expected to reveal general principles that govern ion transport through biological transmembrane channels, a process that is important for intercellular communication and for signal transmission in the nervous system.

离子运输在分子水平的化学性质为 仅一般地理解。 这项研究的目的 是为了增强对快速和选择性离子的理解 通过分子的跨膜通道传输 等级。 Gramicidin渠道家族是一个强大的系统 用于研究离子，蛋白质和脂质之间的相互作用 在运输过程中。 Gramicidin家族代表 相关系列已知结构的肽，其中特定的 结构的变化和可极化的特定位置 取代基可以与通道的选择性，稳定性相关， 脂质依赖性和运输特性。 优势 Gramicidin家族包括：单价的理想选择性 阳离子，部分互化特异性，单文件 特征，其公认的结构，可用性 天然和合成类似物，以及对 本地和模拟构象的等效性。 这项研究 将解决基本步骤的化学控制 使用动力学和平衡技术运输。 地点- Gramicidin通道的特定修饰将用于 （i）研究信道特性和结构功能 关系和（ii）设计扩展的新分子特征 父分子的功能。 结果预计 揭示通过离子运输的一般原则 生物跨膜通道，一个重要的过程 用于细胞间通信和信号传输 神经系统。