基因工程修饰的功能化淀粉样蛋白是新出现的一种具备多种优异性能的纳米结构，在纳米技术和材料科学有广阔的应用前景，但是对于它们的结构和动态自组装机理却知之甚少。本研究以大肠杆菌生物膜中的功能化淀粉样蛋白CsgA为模型，以上海光源的同步辐射X射线衍射(XRD)和小角散射(SAXS)线站为工作平台，表征一系列通过基因工程修饰的功能化淀粉样蛋白的自组装结构，并充分应用同步辐射高强度、快速采样的特点来研究它们的自组装动态过程。最后我们结合高分辨电镜 (HRTEM)、快速原子力显微镜（AFM）和其他表征手段，综合解析在引入不同多肽或蛋白模块后纤维的结构、形貌和自组装动力学的变化。本申请将阐明经过基因工程修饰的CsgA的结构和动态自组装机理，为理性构建以功能化淀粉样蛋白为基的新型功能材料提供理论指导，同时也将丰富和完善淀粉样蛋白的表征手段，并促进功能化淀粉样蛋白纤维在纳米技术和材料科学领域的应用。

Functional amyloids with decorated moieties are emerging tunable nanostructures with many outstanding properties, finding broad applications in nanotechnology and materials science. However, knowledge about detailed molecular structures and their associated self-assembly is poorly understood. In this study, we will leverage the platform of Shanghai Synchrotron Radiation Facility (SSRF) to investigate a series of genetically engineered amyloid proteins derived from CsgA protein, a model functional amyloid system based on E. coli biofilm Curli. Specifically, we propose the use of X-ray Diffraction (XRD) and Small Angle X-ray Scattering (SAXS) to probe the structures and dynamic self-assembly of these engineered CsgA, fused with diverse peptide or protein domains at varied sites. In addition, we will also apply High-Resolution Transmission Electron Microscopy (HRTEM), Atomic Force Microscopy (AFM) and other biological assays to reveal how the differently fused groups affect the morphology and assembly kinetics of amyloids. Collectively, this study will provide new insights into the structural features and molecular self-assembly of genetically engineered CsgA. As natural functional amyloid proteins have been increasingly discovered and more of these modified versions will be utilized as building blocks for constructing functional materials, our systematic investigation on CsgA amyloid system here will therefore lay the foundation to guide the rational design of amyloid-based functional materials in the future. We also believe our research will enrich the characterization of amyloid proteins and promote further applications of functional amyloids in nanotechnology and materials science.