SPECTROSCOPY OF BIOMEMBRANE MONOLAYERS

单层生物膜的光谱学

• 批准号: 6385726
• 负责人: RICHARD A. DLUHY
• 金额: $ 18.88万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-07-01 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6385726
• 关键词: Raman spectrometry; bioimaging /biomedical imaging; biophysics; conformation; fiber optics; fluorescence microscopy; hydropathy; infrared spectrometry; intermolecular interaction; light scattering; lipid structure; membrane model; membrane proteins; membrane structure; molecular film; phase change; phospholipids; protein structure; pulmonary surfactants; surface property

It is the overall aim of the current proposal to employ a combined spectroscopy/imaging approach using IR and Raman spectroscopy as well as fluorescence microscopy for the study of biophysical monolayer models of pulmonary surfactant. A combined approach is needed, since no one method is able to accomplish both structural characterization and morphological imaging for a detailed understanding of conformational and spatial properties in the monolayer. The combination of vibrational spectroscopy and fluorescence imaging will correlate molecular properties with mesoscopic (i.e. mum size) domain morphology in surfactant monolayers. Our recent results suggest that the interaction of surfactant proteins with biomembrane interfaces may occur selectively at locations with distinct morphological properties, such as at domain boundaries or areas of a certain lipid phase. Therefore, investigation of the molecular structural properties of the system, as reported by IR or Raman, in conjunction with its morphological structure, as visualized by fluorescence, is needed to more fully understand the interaction between the system components. The combination of techniques described in this proposal will mark an important achievement for the investigation of the molecular interaction between proteins and lipids in surfactant models in that we will be able to associate specific molecular spectroscopic properties with lateral organization in surface monolayers. During the next grant period, we will address the following specific aims: 1) to characterize the interfacial and hydrophobic interactions of the surfactant proteins SP-B and SP-C on monolayer structure by IR and to determine protein structure in the monolayer by Raman spectroscopy, 2) to characterize the influence of SP-B and SP-C on monolayer morphology by fluorescence microscopy and to determine how these proteins produce three-dimensional, surface-excluded material as seen using scattered light microscopy, 3) to use IR spectroscopy to measure microphase separation and domain formation in binary mixtures, and 4) to use spatially-resolved Raman microscopy to study lateral organization and molecular structure in surfactant monolayer films.

当前提案的总体目标是采用红外和拉曼光谱以及荧光显微镜的组合光谱/成像方法来研究肺表面活性剂的生物物理单层模型。 需要一种组合方法，因为没有一种方法能够同时完成结构表征和形态成像以详细了解单层的构象和空间特性。 振动光谱和荧光成像的结合将分子特性与表面活性剂单层的介观（即最小尺寸）域形态相关联。 我们最近的结果表明，表面活性剂蛋白与生物膜界面的相互作用可能选择性地发生在具有不同形态特性的位置，例如在域边界或特定脂相的区域。因此，需要对系统的分子结构特性（如红外或拉曼报告）及其形态结构（如荧光可视化）进行研究，以更全面地了解系统组件之间的相互作用。 该提案中描述的技术组合将标志着研究表面活性剂模型中蛋白质和脂质之间的分子相互作用的重要成就，因为我们将能够将特定的分子光谱特性与表面单层的横向组织联系起来。 在下一个资助期内，我们将实现以下具体目标：1）通过红外表征表面活性剂蛋白 SP-B 和 SP-C 在单层结构上的界面和疏水相互作用，并通过拉曼光谱确定单层中的蛋白质结构，2）通过荧光显微镜表征 SP-B 和 SP-C 对单层形态的影响，并确定这些蛋白质如何产生三维、 使用散射光显微镜观察表面排除的材料，3) 使用红外光谱测量二元混合物中的微相分离和域形成，4) 使用空间分辨拉曼显微镜研究表面活性剂单层膜中的横向组织和分子结构。