Mechanisms of Protein Protection by Desiccation-tolerance Molecules

通过该奖项，化学部生命过程化学计划资助北卡罗来纳大学教堂山分校的Gary J.Pielak博士研究大小脱水耐受分子所使用的蛋白质保护机制。被选中在干燥中存活的生物是通过制造保护性分子来做到这一点的，但保护机制大多尚不清楚。从实践的角度来看，了解脱水保护将改进生物制造过程和生物产品，如生物药物和工业酶。这些研究将为研究生和本科生提供蛋白质化学和物理生物化学方面的专门培训，这是基础和工业研究的有用技能。PI还将与卡罗莱纳圣约合作，该计划旨在帮助低收入北卡罗来纳大学的学生无债务毕业，以培养学生对化学研究感兴趣。提出的四个主要想法-水分保留、玻璃化、水置换和分子屏蔽假说-将通过结合蛋白质工程、核磁共振光谱、傅立叶变换红外光谱和流变学进行测试。最常见的天然保护性小分子是非还原二糖，海藻糖，但也有几类保护性无序蛋白质。研究最充分的成员是晚期胚胎发生丰富(LEA)蛋白，这种蛋白在植物中发现，但也在动物中发现。最近发现的一类保护蛋白--胞浆丰富热溶蛋白(CAHS)--是迟滞动物所独有的。CAHs蛋白质之所以引人注目，不仅是因为它们保护其他蛋白质和酶，还因为它们形成了保护性凝胶。该项目将比较和对比每一种类型的保护分子，以更好地了解它们的结构如何有助于有机体在脱水条件下的生存。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Dr. Gary J. Pielak from the University of North Carolina at Chapel Hill to investigate mechanisms of protein protection used by large and small desiccation tolerance molecules. Organisms selected to survive desiccation do so by making protective molecules, but the mechanisms of protection are mostly unknown. From a practical perspective, understanding dehydration protection will improve biomanufacturing processes and bio-based products, such as biologic drugs and industrial enzymes. These studies will provide graduate and undergraduate students with specialized training in protein chemistry and physical biochemistry, which are useful skills for basic and industrial research. The PI will also work with the Carolina Covenant, a program that helps low-income UNC students graduate debt-free, to train students interested in chemistry research.The four main ideas proposed to explain desiccation protection — water retention, vitrification, water replacement and molecular shield hypotheses — will be tested by using a combination of protein engineering, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy and rheometry. The most common natural protective small molecule is the nonreducing disaccharide, trehalose, but there are also several classes of protective disordered proteins. The most well-studied members are the Late Embryogenesis Abundant (LEA) proteins, which were discovered in plants but are also found in animals. The most recently discovered class of protective proteins — Cytosolic Abundant Heat Soluble (CAHS) proteins — are unique to tardigrades. CAHS proteins are remarkable not only because they protect other proteins and enzymes but also because they form protective gels. This project will compare and contrast each of these types of protective molecules to better understand how their structures contribute to the survival of organisms under dehydrating conditions.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.