Biosynthesis and function of novel modified heptoses present in bacterial surface polysaccharides

一些细菌用长链糖覆盖其表面，这影响它们与宿主细胞的相互作用以及它们在环境中或在新宿主的定殖期间遇到的不利生长条件下存活的能力。这些糖有时可能非常不寻常。它们的确切功能和它们影响与宿主细胞相互作用的机制尚不清楚。为了更好地了解它们的功能，有必要确定其合成所必需的基因，以及表征由基因编码的酶。我们专注于在几种细菌（耶尔森氏菌，弯曲杆菌）的表面上发现的不寻常的庚糖，并且使用耶尔森氏菌作为模型系统在阐明其生物合成和功能方面取得了很大进展。我们建议使用弯曲杆菌进行研究，因为不寻常的庚糖是弯曲杆菌中不同类型的表面大分子的一部分。在我们的研究中收集的基础知识将帮助我们了解特定的糖如何影响大分子的功能，这是糖生物学领域的核心问题，不仅适用于细菌，也适用于植物和动物。我们还计划对我们已经确定的酶进行广泛的结构/功能研究，因为这将为设计可能具有技术应用的新型糖衍生物提供新的工具

Some bacteria cover their surface with long chains of sugars that affect their interactions with host cells and their ability to survive to adverse growth conditions encountered in the environment or during the colonization of a new host. These sugars can sometimes be very unusual. Their exact function and the mechanism whereby they affect interactions with host cells are not known. To better understand their function, it is necessary to identify the genes that are necessary for their synthesis, as well as to characterize the enzymes that are encoded by the genes. We are focusing on unusual heptoses that are found on the surface of several bacteria (Yersiniae, Campylobacters) and have made great progress in elucidating their biosynthesis and function using Yersiniae as a model system. We propose to pursue our studies using Campylobacters as the unusual heptoses are part of a different type of surface macromolecule in Campylobacters. The fundamental knowledge gathered in our studies will help us understand how a specific sugar can affect the function of a macromolecule, a question that is at the heart of the field of glycobiology and that applies not only to bacteria but also to plants and animals. We also plan to perform extensive structure/function studies of the enzymes that we have identified as this will provide novel tools to engineer novel sugar derivatives that could have technological applications