疏水蛋白自组装和粘附的机理研究

Hydrophobins are a special class of amphiphilic proteins produced by filamentous fungi. They show outstanding interfacial self-assembly and adhesion properties, which are critical to their biological function. Such feature also inspires their broad applications in bio-engineering, surface modification, and nanotechnology. However, the biophysical properties of hydrophobins are not well understood. Although there are some studies on the conformational change and oligomerization of hydrophobins in diluted solution as well as the structure of hydrophobin monomers and self-assemblied membranes, the quantitative measurement of the adhesion stength and self-assembling kinetics has not been reported. In this project, we plan to combine atomic force microscope based single molecule force spectroscopy and fast imaging with protein engineering to directly quantify the adhesion strength of hydorphobin to various kinds of surfaces in both the monomer and the oligomer states. By comparing the adhesion behaviors of different hydrophobins, the molecular determinant of the adhesion strength of hydrophobins will be revealed. We will further elucidate how different environmental conditions, such as ionic strength, pH and the presence of organic solvents, affect the self-assembly and adhesion of hydrophobins. Especially, we will use hydrophobin as a model system to study how microenvironment affect hydrophobic interactions. These studies will serve as the basis for further exploring the applications of hydrophobins in bio-engineering, self-assembly, surface modification and nanotechnology.

疏水蛋白是在丝状真菌中发现的一类具有双亲性的特殊蛋白，在固液、气液界面具有优良的自组装和粘附性能。这一特点也启发了其在生物工程、表面修饰、纳米技术等很多领域的广泛应用。然而目前人们对疏水蛋白的生物物理特性的研究还主要集中于其在稀溶液中的构象变化、寡聚体的形成、以及自组装膜的形成以及结构等方面，对疏水蛋白在界面的粘附力及其物理机制的探索非常有限。本项目拟通过基于原子力显微镜的单分子力谱、快速成像结合蛋白质工程技术，定量表征两种典型的疏水蛋白单体以及自组装体在不同的固体表面的粘附强度，揭示疏水蛋白结构与粘附性能之间的关系，研究各种环境因素、如离子强度、pH值以及有机溶剂等对其在不同表面的粘附能力的调控，探索疏水蛋白自组装膜形成的物理机制和影响因素，并以疏水蛋白为模型，探索疏水相互作用与微观环境之间的关系，为进一步拓展疏水蛋白在生物工程、化学自组装、表面修饰和纳米技术等领域的应用提供新的思路。

疏水蛋白是在丝状真菌中发现的一类具有双亲性的特殊蛋白，在固液、气液界面具有优良的自组装和粘附性能。这一特点也启发了其在生物工程、表面修饰、纳米技术等很多领域的广泛应用。然而目前人们对疏水蛋白的生物物理特性的研究还主要集中于其在稀溶液中的构象变化、寡聚体的形成、以及自组装膜的形成以及结构等方面，对疏水蛋白在界面的粘附力及其物理机制的探索非常有限。本项目通过基于原子力显微镜的单分子力谱、快速成像结合蛋白质工程技术，定量表征两种典型的疏水蛋白单体以及自组装体在不同的固体表面的粘附强度，揭示疏水蛋白结构与粘附性能之间的关系，研究各种环境因素对粘附能力的调控，探索疏水蛋白自组装膜形成的物理机制和影响因素，并以疏水蛋白为模型，探索了疏水相互作用与微观环境之间的关系，为进一步拓展疏水蛋白在生物工程、化学自组装、表面修饰和纳米技术等领域的应用提供新的思路，设计制备多种具有优良特性的软物质材料。在项目的资助下，发表学术论文22篇，申请专利2项，培养博士生7名，硕士生4名。