CAREER: Functional Structure and Dynamics of Complex Carbohydrates Via Sensitivity-Enhanced Solid-State NMR and Database Development

复杂的碳水化合物对许多生物过程至关重要，如能量储存、分子结构的构建和细胞识别。碳水化合物的结构复杂性决定了它们的物理和化学性质，但也为高分辨率结构表征提出了技术障碍。在这个跨越化学、生物学和计算机科学的跨学科项目中，新的方法将被开发出来，以获得对天然细胞环境中多糖功能-结构关系的原子和分子水平的洞察。该研究将揭示微生物如何构建细胞壁的基本原理，这将促进基于碳水化合物/靶向生物材料和抗真菌药物的发展。生物物理方法和数据库开发的进步将使研究界受益，并为进一步研究来自各种生物（如藻类、细菌、植物和动物）的碳水化合物奠定基础。由于路易斯安那州是生物分子核磁共振装备最落后的州之一，新的课程和拓展计划将使学生接触光谱和数据库，这将扩大该州的研究能力，并促进下一代生物物理科学家的培训。在这个项目中，PI将开发创新的方法，将数据库和软件开发与固态核磁共振和动态核极化（DNP）光谱相结合，从而能够对完整细胞中的复杂碳水化合物进行结构分析。该团队将开发一种样品筛选方案和DNP工具箱，以便对未标记的全细胞进行结构解析，从而克服由于同位素标记的难度和费用而存在的长期障碍。此外，该项目将在碳水化合物数据库中实现两个新功能，以方便结构分析，并确定四种霉菌和酵母中多糖的超分子组装。本项目将解决不溶性和无序聚糖在天然状态下的多态性结构，从而填补了碳水化合物化学和生命科学领域长期存在的空白。PI将从事广泛传播教育和外联活动，包括(i)为研究生课程开发固态核磁共振理论和实验课程；（ii）为本科生实验室设计了“碳水化合物指纹”实验模块，并为高中生设计了两个拓展项目；（三）支持学生旅行，以获得国家最先进设施的经验，并与领先的专家互动；（四）培养不同科学专业的本科生进行跨学科研究；(v)通过“设计错误”和“学生同侪教学”的新教学方法，提高课程参与度和主动学习；（六）编码数据库和分析软件，使研究界受益。这种坚定的承诺将使博士后，研究生，本科生和K-12学生，许多来自代表性不足的少数民族，有机会接触到生物物理和生物分子研究的前沿。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。

Complex carbohydrates are essential to many biological processes such as energy storage, building of molecular structures, and cell recognition. The structural complexity of carbohydrates determines their physical and chemical properties but also presents a technical barrier to high-resolution structural characterizations. In this interdisciplinary project across chemistry, biology and computer science, new methodologies will be developed to obtain atomic- and molecular-level insight onto the function-structure relationship of polysaccharides in native cellular environments. The research will reveal the fundamental principles of how microbes construct their cell walls, which will promote the development of carbohydrate-based/targeted biomaterials and antifungal agents. The advances in biophysical methods and database development will benefit the research community and set up the stage for further investigations of carbohydrates from various organisms such as algae, bacteria, plants, and animals. As Louisiana is one of the most under-equipped states in biomolecular NMR, the new courses and outreach programs will allow students to gain exposure to spectroscopy and database, which will expand the research capability of the state and foster the training of the next generation of biophysical scientists.In this project, the PI will develop innovative methods that integrate database and software development with solid-state NMR and Dynamic Nuclear Polarization (DNP) spectroscopy to enable structural analysis of complex carbohydrates in intact cells. The team will develop a sample screening protocol and DNP toolbox to enable structural elucidation of unlabeled whole-cells and thus overcome a long-standing barrier due to the difficulty and expense of isotope-labeling. In addition, the project will implement two new functions to a carbohydrate database to facilitate structural analysis, and determine the supramolecular assembly of polysaccharides in four molds and yeasts. This project will resolve the polymorphic structure of insoluble and disordered glycans in their native state, thus filling a long-standing gap in carbohydrate chemistry and life science. The PI will engage in a broad dissemination of education and outreach activities, including (i) developing a solid-state NMR course on theory and experimentation for graduate curriculum; (ii) designing an experimental module 'Fingerprints of Carbohydrates' for undergraduate laboratory and two outreach programs for high school students; (iii) supporting student travel to gain experience on the state-of-art national facilities and interact with leading experts; (iv) training undergraduates from diverse scientific majors to conduct interdisciplinary research; (v) enhancing course engagement and active learning through new teaching methods 'designed mistakes' and 'students peer-teaching'; and (vi) coding database and analytical software to benefit the research community. This strong commitment will allow postdoc, graduate, undergraduate and K-12 students, many from underrepresented minorities, to gain exposure to the frontiers of biophysical and biomolecular research.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.