Protein Glycosylatin in Haemophilus ducreyi

杜克雷嗜血杆菌中的蛋白糖基化蛋白

基本信息

批准号：
7267915
负责人：
ROBERT S. MUNSON
金额：
$ 17.48万
依托单位：
RESEARCH INST NATIONWIDE CHILDREN'S HOSP
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-07-01 至 2009-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7267915
关键词：
Anabolism Bacterial Adhesins Biology Campylobacter coli Carbohydrates Data Depth Development Disaccharides Disease Enzymes Escherichia coli Adhesins Fimbriae Proteins Flagellin Gene Proteins Genes Genetic Screening Genital system Glycoconjugates Glycoproteins Goals Haemophilus influenzae Hemophilus ducreyi Human Immunity Infection Laboratories Learning Libraries Metabolism Modeling Molecular Weight Neisseria gonorrhoeae Neisseria meningitidis Organism Pathogenesis Play Prevention Protein Glycosylation Proteins Pseudomonas aeruginosa Research Personnel Role Role playing therapy Sialic Acids Sialyltransferases Structure Thinking Ulcer Virulence Western Blotting base carbohydrate structure design glycosylation glycosyltransferase in vitro Model insight lipooligosaccharide mutant novel strategies pathogen programs research study sialic acid permease

项目摘要

DESCRIPTION (provided by applicant): Haemophilus ducreyi is the causative agent of chancroid, a sexually transmitted genital ulcerative disease. The pathogenic mechanisms responsible for ulcer formation and immunity to H. ducreyi infection are poorly understood. We previously characterized many of the genes encoding glycosyltransferases responsible for synthesis of the major glycoforms of H. ducreyi lipooligosaccharide (LOS). One of the genes identified in these studies is the LOS sialyltransferase. We recently extended our characterization of sialic acid metabolism in H. ducreyi by designing and executing a genetic screen that identified genes encoding the sialic acid transporter. In addition to identifying the transporter, we observed that H. ducreyi produces a non-LOS glycoconjugate containing terminal Gal-?1-4-GlcNAc. Western blot data suggests that this terminal Gal-GlcNAc disaccharide decorates a protein. Although much has been learned about Gram-negative glycoproteins in the last several years, it is apparent that we have just begun to understand the mechanisms of synthesis of these glycoconjugates and the roles that they play in the biology of pathogenic organisms and bacterial-host interactions. In this proposal, we describe experiments designed to identify the H. ducreyi glycoprotein, identify the composition of the complete carbohydrate decorating the protein and identify the genes encoding the enzymes responsible for glycosylation of this protein. These studies will form the basis for an R01 application that will examine, in depth, the structure, biosynthesis and function of the carbohydrate decoration on the H. ducreyi protein. Studies will also be proposed in that R01 application to determine the role of the protein in virulence using both in vitro models as well as the human challenge model developed in Stanley Spinola's laboratory. Identification of the protein will likely provide additional insight into the poorly understood pathogensis of chancroid, will provide new data that will contribute to our increasing understanding of bacterial glycoproteins and the role they play in bacterial pathogenesis and immunity, and may also provide insight into the development of novel strategies for prevention of H. ducreyi infection.

描述（由申请人提供）：杜克雷嗜血杆菌是软下疳的病原体，软下疳是一种性传播的生殖器溃疡病。对溃疡形成和杜克雷螺杆菌感染免疫的致病机制知之甚少。我们之前描述了许多编码糖基转移酶的基因，这些糖基转移酶负责合成 H. ducreyi 脂寡糖 (LOS) 的主要糖型。这些研究中发现的基因之一是 LOS 唾液酸转移酶。我们最近通过设计和执行鉴定编码唾液酸转运蛋白的基因的遗传筛选，扩展了杜克雷酵母唾液酸代谢的表征。除了鉴定转运蛋白之外，我们还观察到 H. ducreyi 产生含有末端 Gal-β1-4-GlcNAc 的非 LOS 糖缀合物。蛋白质印迹数据表明，这种末端 Gal-GlcNAc 二糖修饰了蛋白质。尽管在过去几年中人们对革兰氏阴性糖蛋白有了很多了解，但显然我们才刚刚开始了解这些糖复合物的合成机制以及它们在病原生物生物学和细菌-宿主相互作用中发挥的作用。在本提案中，我们描述了旨在鉴定 H. ducreyi 糖蛋白、鉴定修饰蛋白质的完整碳水化合物的组成以及鉴定编码负责该蛋白质糖基化的酶的基因的实验。这些研究将构成 R01 应用的基础，该应用将深入研究 H. ducreyi 蛋白上碳水化合物修饰的结构、生物合成和功能。还将在 R01 应用中提出研究，利用体外模型以及 Stanley Spinola 实验室开发的人类挑战模型来确定蛋白质在毒力中的作用。该蛋白质的鉴定可能会为人们对软下疳的发病机制知之甚少提供更多的见解，将提供新的数据，有助于我们加深对细菌糖蛋白及其在细菌发病机制和免疫中所发挥的作用的了解，并且还可能为了解软下疳的发展提供见解。预防杜克雷螺杆菌感染的新策略。