Modular Synthesis of N-Glycans and Homogeneous Glycoproteins

化学部的化学合成计划支持由斯克里普斯研究所的Chi-Huey Wong教授领导的项目。他的团队专注于开发一种新的化学和酶促方法的组合，用于合成复杂的寡糖，这些寡糖将被连接到蛋白质上，以形成同质的糖蛋白，如抗体。人类和其他高等生物体中的大多数蛋白质都有各种糖连接，形成一个异质的糖蛋白群体。因此，很难理解糖在糖蛋白中的作用。该项目建立了合成复杂寡糖的有效方法，并将其用于组装含有明确寡糖结构的均质糖蛋白。 获得这些同质糖蛋白使我们能够了解寡糖如何影响蛋白质的功能，以及如何将更好的糖蛋白作为药物或试剂。这个多学科项目为年轻科学家的培训提供了丰富的环境。了解糖基化对蛋白质折叠，结构和功能的影响在生物学和医学中至关重要，需要获得大量复杂的N-聚糖。 这些寡糖可以使用该项目中描述的模块化方法组装，该方法将N-聚糖合成的任务分解为分支模块的化学酶制剂和核心单元的化学合成。 分支模块的合成（具体目标1）从七个合成中间体开始，这些中间体可以使用酶促转化来多样化，以产生许多模块。正在优化核心寡糖的化学合成，以提供针对特定应用定制的N-聚糖，从而提高该方法的实用性（具体目标2）。 使用合成N-聚糖样品，制备代表性单克隆抗体的新糖型，用于研究其活性（具体目标3）。本研究中开发的所有模块、酶和试剂都可供社区使用，以促进我们对蛋白质糖基化的理解，并推动糖科学的研究。

The Chemical Synthesis Program of the Chemistry Division supports the project led by Professor Chi-Huey Wong at The Scripps Research Institute. His group focuses on the development of a new combination of chemical and enzymatic methods for the synthesis of complex oligosaccharides to be attached to proteins to form homogeneous glycoproteins such as antibodies. Most of the proteins in humans and other higher organisms have various sugars attached to form a heterogeneous population of glycoproteins. As a result, it has been difficult to understand the roles sugars play in glycoproteins. This project establishes effective methods for the synthesis of complex oligosaccharides and their use in the assembly of homogeneous glycoproteins containing well defined oligosaccharide structures. Access to these homogeneous glycoproteins allows us to understand how the oligosaccharide affects the functions of proteins and how to make better glycoproteins as medicines or as reagents. This multidisciplinary project presents a rich environment for the training of young scientists.Understanding the effect of glycosylation on protein folding, structure and function is vitally important in biology and medicine and requires access to a large number of complex N- glycans. These oligosaccharides could be assembled using the modular method described in the project, which breaks down the task of N-glycans synthesis into the chemoenzymatic preparation of branched modules and the chemical synthesis of the core unit. The synthesis of branched modules (Specific Aim 1) begins with seven synthetic intermediates, which can be diversified using enzymatic transformations to generate a number of modules. Chemical synthesis of the core oligosaccharide is being optimized to provide N-glycans tailored to a specific application, therefore increasing the utility of this method (Specific Aim 2). Using the synthetic N-glycan samples, new glycoforms of a representative monoclonal antibody are being prepared for the study of their activities (Specific Aim 3). All modules, enzymes, and reagents developed in this study are made available to the community to facilitate our understanding of protein glycosylation and to advance the research in glycoscience.