Activation of Biofunctional Molecules Induced by Binding of Glycomolecules

首先，研究了在温和条件下寡糖与多肽结合的反应。在37℃的温度下，以三硼酸钠为还原剂作用数小时，发现具有2-7个葡萄糖残基的麦芽寡糖为聚赖氨酸或聚精氨酸的氨基。由于在反应产物的NMR谱中，聚苯胺侧链的ε -碳的吸收在40.9ppm时从原来的位置转移到50.2ppm，因此确定了各峰强度的比值。通过使用10个等量的低聚糖如麦芽糖和麦芽糖戊糖，发现了85-90%的高取代度的反应条件。接下来，将低聚糖与天然酶如醛缩酶、乳酸脱氢酶、6-磷酸葡萄糖脱氢酶、胆碱酯酶和磷酸酶碱氨酸结合。除醛缩酶（9%）外，所有糖结合酶的活性均恢复到原来的58-90%。在麦芽糖或麦芽糖七糖结合磷酸酶碱性的情况下，发现10-20天后的酶活性远远大于原始磷酸酶碱性的酶活性。此外，为了研究多糖与蛋白质相互作用的机制，用核磁共振测量了硫酸凝血素、肝素和硫酸软骨素等多糖与聚赖氨酸、聚精氨酸等多肽及其共聚物的各种混合物。

First, the reaction which binds oligosaccharides to peptides in mild conditions was examined. Malto-oligosaccharides having 2-7 glucose residues were found to the amino group of polylysine or polyarginine as protein model compounds by use of sodium cyanoborohydrate as a reducing agent at 37ﾟC for several hours. Since in NMR spectra of the reaction products, absorptions due to epsilon-carbon of poiyilsine side chains shifted from the original position at 40.9ppm to 50.2ppm, the ratio of each peak intensity was determined. Reaction conditions affording high degrees of substitution of 85-90% were found by using 10 equivalents of oligosaccharides such as maltose and maltopentaose.Next, bindings of oligosaccharides to natural enzymes such as aldolase, lactate dehydrogenase, 6-phosphogluconic dehydrogenase, cholinesterase, and phosphatase slkaline were performed. All sugar bound-enzymes except for aldolase (9%) exhibited58-90% of their original activities. In the case of maltose or maltoheptaose bound-phosphatase alkaline, it was found that, the enzyme activity after 10-20 days was much larger than that of the original phosphatase slkaline.In addition, to examine mechanisms of interactions of poilsaccharides with proteins, various mixtures of suifated polysaccharides such as curdlan sulfate, heparin, and chondroitin sulfate with polypeptide like polylysine, polyarginine, and their copolymers were measured by NMR.