Affinity Preparation of Sialylsulfo-glycopeptides from Hen Ovomucin and Their Characteristic Analysis

a.通过碱性硼氢化反应从蛋清中释放糖链。用离子交换色谱法分离了中性和酸性糖链。采用Bio-Gel P-4凝胶过滤纯化中性糖链。采用离子交换和高效液相色谱法纯化了酸性糖链。通过甲基化和核磁共振分析分析了糖链的化学结构。最后澄清了三个新的中性糖链（单糖、二糖和三糖）和三个新的酸性糖链（四糖、五糖和六糖）。卵黄蛋白由actinase消化，中性和酸性糖肽（唾液酰糖肽和唾液酰磺基糖肽）由我们在之前的文章中建立的溶菌酶亲和层析分离。用聚苯乙烯珠评价霍乱毒素中和活性的新方法。与微孔板法相比，该系统具有更高的灵敏度。用溶菌酶亲和层析法从母鸡卵黄蛋白中分离得到的唾液酰和唾液酰磺基糖肽对霍乱毒素具有较高的中和活性。

a. Sugar chains were released from hen ovomucin by alkaline borohydride reaction. Neutral and acidic sugar chains were isolated by ion-exchange chromatography. Neutral sugar chains were purified Bio-Gel P-4 gel filtration. Acidic sugar chains were purified by ion-exchange and high performance liquid chromatographies. The chemical structures of sugar chains were analyzed by methylation and nuclear magnetic resonance analysis.b. Three novel neutral sugar chains (mono-, di- and trisaccharide) and three novel acidic sugar chains (tetra-, penta- and hexasaccharide) were finally clarified.c. Ovomucin was digested by actinase E.Neutral and acidic glycopeptides (sialyl- and sialylsulfo-glycopeptides) were separated by lysozyme-affinity chromatography which was developed in our previous paper.d. A new assay for evaluation of neutralizing activity against cholera toxin by using polystirene beads. This system was more high sensitive compared to microplate method.e. Sialyl- and sialylsulfo-glycopeptide isolated from hen ovomucin by lysozyme-affinity chromatography showed high neutralizing activity against cholera toxin.