Molecular Biomechanics of Fibrous Proteins and Related Biopolymer Systems.

我的实验室研究结构生物聚合物的分子生物力学。我们的目标是了解分子结构，物理化学，机械性能和生物功能之间的关系。然而，我们敏锐地意识到，我们收集的基础科学可以通过基因工程用于开发新的结构蛋白，也可以通过模仿自然界的设计为开发新技术提供方向。在目前的提案中，我们将研究以下几种生物聚合物系统。1. 高性能蛋白纤维：我们将通过研究丝素蛋白序列对蜘蛛拖丝力学性能应变速率依赖性的影响，继续致力于基因工程蚕丝的开发。到目前为止，几乎所有关于蜘蛛丝的力学研究都是通过低应变率测试协议来量化性能的，但是这些蛛丝在蛛网和安全线中都是动态的，在那里它们经历了非常高的应变率。一种新的冲击测试仪将使我们能够在测试条件下评估影响这些非凡材料演变的机械功能的材料性能。我们还将继续研究中间长丝（IF）基材料及其拉伸转化成丝状纤维的研究。我们的重点将是开发基于二酪氨酸和谷氨酰胺转氨酶的共价交联工艺，用于调节性能和纤维增强复合材料组装。2. 类似橡胶的蛋白质和复合材料：几十年来，我们一直在研究弹性蛋白的结构和性质，以及动脉的功能设计。我们将继续这项重要的工作，对小鼠主动脉的单个弹性薄片进行力学和结构分析，这将为我们最近发现的胸主动脉弹性蛋白特性梯度提供见解。我们将与UBC的李宏斌博士合作，继续研究基于弹性的材料。我们的工作将包括电纺丝或纤维基长丝制成弹性水凝胶，创造具有组织工程潜力的纤维增强弹性复合材料。

My lab investigates the molecular biomechanics of structural biopolymers. Our goal is to understand relationships between molecular structure, physical chemistry, mechanical properties and the function in living organisms. However, we are keenly aware that the basic science we gather can be used in the development of new structural proteins through genetic engineering and also can provide direction for the development on novel technologies by mimicking designs found in Nature. In the current proposal we will investigate the following kinds of biopolymer systems. 1. High-performance protein fibers: We will continue our efforts on the development of genetically engineered silks by investigating the role of silk fibroin sequence on the strain-rate dependence of mechanical properties in spider dragline silks. Virtually all mechanical studies with spider silks to date have quantified properties with low strain-rate testing protocols, but these silks function dynamically in both webs and in safety lines, where they experience very high strain rates. A new impact tester will allow us to evaluate material properties under test conditions that span the mechanical functions that have influenced the evolution of these remarkable materials. We will also continue our investigations of intermediate filament (IF) based materials and their draw-transformation into silk-like fibers. Our focus will be on the development of di-tyrosine and transglutaminase-based covalent crosslinking processes for modulating properties and for fibre-reinforced composite assembly. 2. Rubber-like proteins and composites: we have worked for decades on the structure and properties of elastin and the functional design of arteries. We will continue this important work with mechanical and structural analyses of the single elastic lamellae from mouse aorta, which will provide insights into our recent discovery of elastin property gradients in the thoracic aorta. We will continue our studies of resilin-based elastic materials in collaboration with Dr. Hongbin Li at UBC. Our role will involve electro-spinning silk or IF-based filaments into resilin hydrogels, creating fiber-reinforced elastic composites that have potential for tissue engineering.