RII-Track 4: Elucidating the Structure and Interactions of Complex Carbohydrates in Fungal and Plant Cell Walls via Dynamic Nuclear Polarization Solid-State NMR

复杂碳水化合物是植物、真菌、细菌和藻类等多种生物细胞壁的基本构建单位，是生物能源和生物材料的主要来源，也是医学治疗的潜在目标。这些多糖在其天然状态下通常是多态和无序的，然而，由于技术限制，它们的功能结构仍未得到充分研究。EPSCoR项目将加强路易斯安那州立大学和国家高磁场实验室（NHMFL）之间的合作努力，旨在开发一种新的方法来解决与多糖相关的几个基本科学问题。具体而言，本研究将促进对碳水化合物与其他生物分子相互作用的趋势和机制以及细胞壁的构建原理和保守模块的理解。这些分子的见解将指导富含碳水化合物的复合材料的设计和工程，以满足国家对更好的生物燃料、材料和生物医学的多样化需求。该合作项目还使科学家和学生能够经常接触到最先进的磁铁设备，在NHMFL进行培训，并引入一种新技术，这将建立路易斯安那州的研究能力。该项目旨在扩大对碳水化合物研究的知识，从纯化组分中的可溶性或结晶分子到天然细胞中高度多态，不溶性和无序的聚糖。这一目标将通过整合动态核极化（DNP）技术和固态核磁共振方法来实现，以最小的扰动表征复杂碳水化合物的结构和组装。通过结合DNP的灵敏度增强和光谱编辑的分辨率提高，PI将能够在复杂的全细胞系统中进行特定位点的多糖研究。结构表征将从13C， 15n标记的组织开始，然后逐步扩展到未标记的材料。这种方法一旦确立，将减轻通常与同位素标记有关的困难和费用，从而克服大规模结构阐明的长期障碍。为了能够快速获取结果，将建立一个数据库来记录多糖的核磁共振观察结果和结构限制，以及细胞壁和其他生物材料的不同结构。所提出的方法和数据库有可能促进富含碳水化合物的复合材料的改性，以满足国家对更好的生物能源和材料的需求。该合作项目还为一名教师和一名博士后提供了在国家高磁场实验室（NHMFL）使用高场核磁共振和DNP磁铁的机会，并通过与知名专家的广泛互动提供了宝贵的学习经验，从而刺激了下一代科学家的职业发展。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-Technical description The complex carbohydrate is a fundamental building unit of cell walls in a variety of organisms such as plants, fungi, bacteria and algae, which serve as a central source for bioenergy and biomaterials as well as a potential target of medical therapies. These polysaccharides are often polymorphic and disordered in their native state, however, due to technical limitations their functional structure remains under-investigated. This EPSCoR project will strengthen the collaborative efforts between Louisiana State University and National High Magnetic Field Laboratory (NHMFL), with the aim of developing a novel method to address several fundamental scientific questions that are related to polysaccharides. Specifically, the proposed research will advance understanding of the tendency and mechanism for carbohydrates to interact with other biomolecules as well as the building principles and conserved modules of cell walls. These molecular insights will guide the design and engineering of carbohydrate-rich composites to fulfill the diverse needs of the nation for better biofuel, material, and biomedicine. This collaborative project also allows scientists and students to gain frequent exposure to state-of-art magnet facilities, training at NHMFL and introduce a new technique that will build up the research capacity of Louisiana. Technical descriptionThis project aims to expand knowledge of carbohydrate research from soluble or crystalline molecules in purified components to the highly polymorphic, insoluble and disordered glycans in native cells. This goal will be achieved by integrating Dynamic Nuclear Polarization (DNP) technique and solid-state NMR methods to characterize the structure and the assembly of complex carbohydrates with minimal perturbation. By combing the sensitivity enhancement from DNP and the resolution improvement from spectral editing, the PI will be able to conduct site-specific investigations of polysaccharides in a complex whole-cell system. Structural characterizations will start from 13C,15N-labeled tissues and then progressively extend to unlabeled materials. This approach, once established, will alleviate the difficulty and expense that is typically associated with isotope-labeling, thus overcoming a long-standing barrier to large-scale structural elucidation. To enable rapid access to the results, a database will be established to document the NMR observables and structural restraints of polysaccharides as well as the diverse architecture of cell walls and other biomaterials. The proposed method and database has the potential to facilitate the modification of carbohydrate-rich composites to serve national demand for better bioenergy and materials. This collaborative project also provides a faculty and a postdoctoral fellow with the access to high-field NMR and DNP magnets at National High Magnetic Field Laboratory (NHMFL) and grants invaluable learning experiences through extensive interactions with well-established experts, thus stimulating the career development of next-generation scientists.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.