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

获得结构定义的N-糖链的文库是快速分析糖链阵列的迫切科学需要 碳水化合物结合蛋白(CBPS)，许多疾病的诊断和治疗的发展。然而，只有一个 目前商业上可以买到少量的N-葡聚糖，这阻碍了糖生物学的研究。 这一应用将通过化学酶法制备80个N-糖链(杂合型、线型和复合型)的文库，并 把它们商业化。长期目标是生产数以千计的天然N-糖聚糖，用于碳水化合物的高通量 化验。首先，基本的N-葡聚糖前体将通过化学合成或以克为单位制备 从鸡蛋中分离出蛋黄和白色。然后，这些N-糖链将被酶促延长或消化，得到80% 不同结构的N-葡聚糖(1 Mg)，其中目前只有12个N-葡聚糖可从 商业消息来源。N-糖链含有5-11个单糖残基。这一过程涉及几口井 具有糖基转移酶、糖苷水解酶等酶的特性。所有N-葡聚糖的纯度都将达到98%， 并用核磁共振和质谱仪进行了充分的表征。

Access to a library of structurally defined N-glycans is an urgent scientific need for glyco-arrays for rapid analysis of carbohydrate binding proteins (CBPs), development of diagnostics and therapeutics for many diseases. However, only a small number of N-glycans are currently commercially available, which hampered researches in Glycobiology. This application will chemo-enzymatically prepare a library of 80 N-glycans (hybrid-, linear and complex-type) and commercialize them. The long-term goal is to produce thousands of natural N-glycans for carbohydrate-based highthroughput assays. Firstly, essential N-glycan precursors will be prepared in gram scales via either chemical synthesis or isolation from chicken eggs yolk and white. These N-glycans will then be enzymatically elongated or digested to yield 80 different N-glycans with defined structures (1 mg), among which only 12 N-glycans are currently available from commercial sources. The N-glycans contain 5 to 11 monosaccharide residues. This process involves several well characterized glycosyltransferases, glycoside hydrolases and other enzymes. All the N-glycans will be purified to 98%, and fully characterized by NMR and MS.