Activated Sugars, Oligosaccharides and Glycans for Antiviral Research

摘要 该项目的目标是开发新的方法来生产糖积木、低聚糖、 以及支持和合理大规模发展病毒糖生物学相关研发所需的葡聚糖 价格。这项技术将支持研究病毒病理学、病毒结合分析和 与宿主的互动，开发新型抗病毒疗法和疫苗的研究，以及其他。 糖生物学在病毒研究的许多方面都很重要。病毒表面蛋白通常大量存在 糖基化以避免被宿主细胞识别，在某些情况下，与宿主受体相互作用。为 例如，SARS-CoV-2病毒的尖峰蛋白糖基化通常是N-连锁核心的延伸 五糖化合物，由壳二糖的茎和甘露糖组成，形成两个触角 复合体。了解病毒S蛋白的糖基化及其潜在的表位掩蔽是 疫苗研究的根本重要性。许多病毒识别的受体都是糖基化的。 蛋白质也是。SARS-CoV-2等使用血管紧张素转换酶2(ACE2)作为其受体，以及 其他b型冠状病毒利用细胞糖蛋白上的唾液酸残基作为受体。 目前，人们正在研究葡聚糖作为疫苗来对抗病毒(登革热、丙型肝炎)、寄生虫 (疟原虫)和真菌(念珠菌)。人乳低聚糖(HMOS)已被证明可以减少 由于干扰致病细菌和潜在病毒的黏附而有感染的可能性。 Galectins已被证明具有促病毒或抗病毒的特性，并在先天免疫中发挥重要作用。 最后，一些半乳糖凝集素抑制剂可能会阻断艾滋病毒对T细胞的感染。低聚糖目前被分离出来 或通过一系列复杂的保护和解除保护步骤以极低的产率合成。 低聚糖和酶法构建它们所需的活性糖构建块在 更大的数量来支持和催生这一重要领域的更多研究。 在可行性研究中，我们成功地展示了一套新型酶的开发，以 生产一系列重要的低聚糖所需的关键活性糖组分。我们 然后演示了使用这些活化的糖来延长模型低聚糖链。在第二阶段 工作中，我们将扩大所有这些活性糖的生产规模，扩大生产系统 需要额外的活性糖，并使一些对病毒生物学重要的关键寡糖 研究。在第二阶段研究期间生产的产品将分发给调查人员，并在第三阶段 产品将作为我们研究试剂目录的一部分进行商业化，或通过进行定制合成 第三方使用的低聚糖。

SUMMARY The goal of this project is to develop novel methods to produce sugar building blocks, oligosaccharides, and glycans needed to support and grow R&D related to viral glycobiology at large scale and reasonable prices. This technology will support researchers studying viral pathology, analyses of viral binding and interactions with hosts, studies to develop novel antiviral therapeutics and vaccines, and others. Glycobiology is important in a number of ways for viral research. Viral surface proteins are often heavily glycosylated to both avoid recognition by the host cell and, in some cases, interact with host receptors. For example, the spike protein glycosylation of the SARS-CoV-2 virus is usually the extension of an N-linked core pentasaccharide compound, composed of a stem of chitobiose followed by mannoses to form two antennary complexes. Understanding glycosylation of viral spike proteins and their potential epitope masking is of fundamental importance for vaccine research. Receptors recognized by many viruses are glycosylated proteins as well. SARS-CoV-2 and others uses angiotensin-converting enzyme 2, (ACE2) as its receptor, and other b-coronaviruses, utilize sialic acid residues on cellular glycoproteins as receptors. Glycans are currently being studied as vaccines against viruses (Dengue, Hepatitis C), parasites (Plasmodium) and fungi (Candida). Human milk oligosaccharides (HMOs) have been shown to reduce the possibility of infections due to interference with adhesion of pathogenic bacteria and potentially viruses. Galectins have been shown have pro- or anti-viral properties and play important role in innate immunity. Finally, some galectin inhibitors may block HIV infection of T cells. Oligosaccharides are currently isolated from nature or synthesized at extremely low yield via a complex set of protection and deprotection steps. Oligosaccharides and the activated sugar building blocks needed to build them enzymatically are needed in larger quantities to support and spawn additional research in this important field. In the Feasibility study we successfully demonstrated the development of a set of novel enzymes to produce a wide range of key activated sugar building blocks required to build important oligosaccharides. We then demonstrated the use of these activated sugars to extend model oligosaccharide chains. In the Phase II work, we will increase the scale of production of all of these activated sugars, extend the system to produce additional activated sugars needed, and make a number of key oligosaccharides important to viral biology research. Products made during the Phase II Research will be distributed to investigators and in Phase III products will be commercialized as part of our research reagent catalog or by carrying out custom synthesis of oligosaccharides for third parties.