天然糖链的提取和糖肽的合成

发布时间：2017-12-31 16:19

本文关键词：天然糖链的提取和糖肽的合成　出处：《南昌大学》2016年硕士论文　论文类型：学位论文

【摘要】：蛋白的糖基化是蛋白质翻译后修饰的一种主要的形式。由于糖蛋白和糖肽的糖链的不均一性,导致其功能上的显著差异。因此,合成均一的糖蛋白和糖肽对于糖链结构和功能的研究是必不可少的。本论文探索了从核糖核酸酶B(RB)、唾液酸糖肽(SGP)和鸡卵清白蛋白(OVA)三种天然来源糖蛋白/糖肽来制备糖链底物的方法,并成功制备了高甘露糖型和复合型两种N-糖链类型的VA唑啉底物。我们选择了10条多肽序列并合成了带乙酰氨基葡萄糖(GlcNAc)的多肽受体,利用了酶催化方法制备了14条高甘露糖型和复合糖型的糖肽。完善了酶催化糖肽合成方法;建立了从RB中提取高甘露糖型糖链及制备相应VA唑啉的半合成方法;探索了从OVA提取糖链的工艺条件和分离条件;制备了可用于糖蛋白质组学分析的标准糖肽。论文第一章概述了糖肽的合成方法、糖苷内切酶法合成糖肽策略的研究以及糖肽化合物的应用。第二章主要叙述了通过半合成法合成糖链供体底物。利用全合成法合成步骤比较繁琐不易纯化,而且很难得到完整的寡糖链供体。本文通过从天然蛋白中分离提取寡糖链,并通过一锅法合成VA唑啉底物,步骤很简短,在分离方面可以减少产物的损失,可以高效地得到糖链给体底物。论文第三章通过Fmoc固相合成法合成了一系列含有GlcNAc的Fmoc保护的天冬酰胺的多肽受体底物。利用Fmoc固相合成法可以简便、快速和高效地得到多肽。第四章通过酶催化反应将合成的糖链供体底物转移到含有GlcNAc的Fmoc保护的天冬酰胺的多肽受体上,高效地合成了均一结构的糖肽。在本章中我们探索了利用天然糖蛋白中提取的并合成新的寡糖链VA唑啉作为糖基供体合成均一糖肽的方法。
[Abstract]:Protein glycosylation is one of the main forms of post-translational modification. Due to heterogeneity of the sugar chain glycoproteins and glycopeptides, lead to significant differences of its function. Therefore, the research on the structure and function of sugar chain synthesis homogeneous glycoproteins and glycopeptides is essential. This thesis explores from ribonuclease B (RB), sialoglycopeptide (SGP) and ovalbumin (OVA) three natural sources of glycoproteins / glycopeptides method for preparing carbohydrate substrates, and prepared VA quinazoline substrate high mannose type and compound type two N- sugar chain type. We chose 10 polypeptide sequences with the synthesis of acetyl glucosamine (GlcNAc) polypeptide receptor, using enzymatic methods for 14 high mannose type and complex type sugar glycopeptides obtained. Improved enzyme catalyzed glycopeptide synthesis method; a preparation phase high mannose type glycans and extracted from RB Semi synthesis method of VA quinazoline; to explore the extraction process of sugar chain from OVA and separation conditions; the preparation can be used for standard glycopeptide sugar proteomics analysis. The first chapter summarizes the synthesis of glycopeptides of endoglycosidase synthesis and application of compound glycopeptide glycopeptide strategy. The second chapter described by semi synthesis of sugar chain donor substrate. Using synthesis steps are more complex and difficult purification, it is difficult to complete the oligosaccharide chain donor. Through extraction and separation of oligosaccharides from natural protein, and through one pot synthesis of oxazoline VA substrate step is very short, the separation can be reduced the product can effectively obtain the loss of sugar chain donor substrates. In the third chapter, the synthesis of a series of Fmoc GlcNAc containing asparagine polypeptide receptor substrate by Fmoc solid-phase synthesis method using. Fmoc solid phase synthesis method can be simple, fast and efficient peptidemaintained. In the fourth chapter, by enzyme catalytic reaction to synthesis of sugar chain asparagine donor substrate transfer to polypeptide receptor Fmoc protection containing GlcNAc on the efficient synthesis of uniform structure of the glycopeptide. In this chapter we explore the method of extracting natural glycoprotein in use and the synthesis of new VA oligosaccharide chain oxazoline as glycosyl donor glycopeptide synthesis of uniform.

【学位授予单位】：南昌大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O629

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