Abstract:
The low sensitivity of nuclear magnetic resonance (NMR) is a major bottleneck for studying biomolecular structures of complex biomolecular assemblies. Cryogenically cooled probe technology overcomes the sensitivity limitations enabling NMR applications to challenging biomolecular systems. Here we describe solid-state NMR studies of the human blood protein vitronectin (Vn) bound to hydroxyapatite (HAP), the mineralized form of calcium phosphate, using a CryoProbe designed for magic angle spinning (MAS) experiments. Vn is a major blood protein that regulates many different physiological and pathological processes. The high sensitivity of the CryoProbe enabled us to acquire three-dimensional solid-state NMR spectra for sequential assignment and characterization of site-specific water-protein interactions that provide initial insights into the organization of the Vn-HAP complex. Vn associates with HAP in various pathological settings, including macular degeneration eyes and Alzheimer\'s disease brains. The ability to probe these assemblies at atomic detail paves the way for understanding their formation.
摘要:
核磁共振(NMR)的低灵敏度是研究复杂生物分子组装体的生物分子结构的主要瓶颈。低温冷却探针技术克服了灵敏度限制,使NMR应用于具有挑战性的生物分子系统。在这里,我们描述了与羟基磷灰石(HAP)结合的人血蛋白玻连蛋白(Vn)的固态NMR研究,磷酸钙的矿化形式,使用为魔角旋转(MAS)实验设计的CryoProbe。Vn是调节许多不同生理和病理过程的主要血液蛋白。CryoProbe的高灵敏度使我们能够获取三维固态NMR光谱以进行顺序分配,以及位点特异性水-蛋白质相互作用的表征,这些相互作用为Vn-HAP复合物的组织提供了初步见解。Vn在各种病理环境中与HAP相关,包括黄斑变性的眼睛和阿尔茨海默病的大脑。以原子细节探测这些组件的能力为理解它们的形成铺平了道路。