论文部分内容阅读
目的:通过对尖吻蝮蛇降纤酶寡糖链的甲基化分析以测定其单糖组成及单糖残基类型。方法:尖吻蝮蛇降纤酶样品用肽:N-糖苷酶F(PNGaseF)酶解释放寡糖链,经过甲基化、水解、还原、乙酰化后,制得其部分甲基化糖醇乙酸酯(PMAAs),衍生化产物用GC-MS分析,以测定其单糖组成和单糖残基类型。结果:样品中含有半乳糖(Gal)、岩藻糖(Fuc)、甘露糖(Man)和N-乙酰葡萄糖胺(GlcNAc)4种单糖。单糖残基类型有末端Gal,末端Fuc,1,2连接、1,2,6连接、1,3,6连接及末端连接的Man,1,4连接及1,4,6连接的GlcNAc。结论:尖吻蝮蛇降纤酶寡糖链中含有Gal、Fuc、Man和Gl-cNAc4种单糖。从单糖残基的类型可知,除了复杂型的N-连接寡糖外,高甘露糖型和/或杂合型N-连接寡糖也存在于降纤酶分子中。
OBJECTIVE: To determine the monosaccharide composition and the type of monosaccharide residue by methylation analysis of the oligosaccharide chain of Agkistrodon acutus. Methods: The sample of Agkistrodon acutus decapitation enzyme was released by enzymatic cleavage of peptide: N-glycosidase F (PNGaseF), and then methylated, hydrolyzed, reduced and acetylated to obtain the partially methylated sugar alcohol Acetate (PMAAs) and derivatized products were analyzed by GC-MS to determine their monosaccharide composition and monosaccharide residue type. Results: The sample contains four kinds of monosaccharides: Gal, Fuc, Man and GlcNAc. The monosaccharide residue types are Man, 1,4, and 1,4,6 linked GlcNAc with terminal Gal, terminal Fuc, 1, 2, 1, 2, 6, 1, 3, 6 and terminal junctions. CONCLUSION: The monoglycerides Gal, Fuc, Man and Gl-cNAc are contained in the oligosaccharide chain of Agkistrodon acutus. From the types of monosaccharide residues, it is known that in addition to the complex N-linked oligosaccharides, high-mannose and / or hybrid N-linked oligosaccharides are also present in the defibrase molecule.