SBIR TOPIC321:CHEMICALLY DEFINED GLYCAN LIBRARIES FOR REFERENCE STANDARDS AND GLY

附着在蛋白质和脂质上的细胞表面寡糖是许多关键性免疫反应中的关键结合表位。 生物过程，包括细菌感染，细胞发育和免疫反应。 在分子水平上理解这些过程需要获得广泛的 已知结构的寡糖，以支持酶底物结合的研究， 特异性，筛选碳水化合物结合蛋白，并开发酶活性测定。 这些低聚糖目前在商业部门无法获得，因此阻碍了在以下方面取得进展： 该领域为了解决这一不足，拟议的项目集中在低聚糖的合成 衍生自母体高甘露糖寡糖（14聚体），将其整体转移至 翻译过程中的多肽。二十八（28）种高甘露糖寡糖，大小范围为 将制备三-至六-氨基甲酸酯。化学路线将用于合成每一种 0.2 mg或更大量的高纯度低聚糖，通过NMR测定，高分辨率 质谱法和高压液相色谱法。个样品 低聚糖，沿着相关的分析数据，将被包装并运送到NCI，用于 构建聚糖阵列以筛选碳水化合物结合蛋白和其他生物化学物质， 或生物医学应用。该第一阶段项目将开发强大的合成方案， 在随后的II期研究中使用，其中化学空间将扩展到六糖之外。 如果没有知识、经验和技术支持， 从拟议的第一阶段工作中获得的专有技术。

Cell-surface oligosaccharides appended to proteins and lipids are key binding epitopes in many critical biological processes, including bacterial infection, cell development and the immune response. Understanding these processes at the molecular level requires access to a wide range of oligosaccharides of known structure to support investigations of enzyme substrate binding and specificity, to screen for carbohydrate binding proteins, and to develop assays for enzymic activity. These oligosaccharides are currently unavailable in the commercial sector, thus impeding progress in this field. To address this deficiency, the proposed project focuses on the synthesis of oligosaccharides derived from the parent high-mannose oligosaccharide (14-mer) that is transferred en-bloc to polypeptides during translation. Twenty-eight (28) high-mannose oligosaccharides ranging in size from tri- to hexa-saccharides will be prepared. Chemical routes will be used to synthesize each oligosaccharide in 0.2 mg or greater quantities and in high purity, as determined by NMR, highresolution mass spectrometry, and high-pressure liquid chromatography. Samples of each oligosaccharide, along with pertinent analytical data, will be packaged and shipped to the NCI for use in the construction of glycan arrays to screen for carbohydrate binding proteins, and for other biochemical or biomedical applications. This Phase I project will develop robust synthetic protocols that will be used in subsequent Phase II studies where the chemical space will be extended beyond hexasaccharides. These latter syntheses will be difficult to conduct without the knowledge, experience and technical know-how gained from the proposed Phase I work.