Structural characterization of the enterococcal polysaccharide antigen and analysis of its contribution to cell growth, division and antibiotic resist

肠球菌多糖抗原的结构表征及其对细胞生长、分裂和抗生素耐药性的贡献分析

• 批准号: 2283067
• 金额: --
• 依托单位: University of Sheffield
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2283067
• 关键词: Structural; characterization; enterococcal; polysaccharide; antigen

The proposed project is focused on the functional analysis of a surfacerhamnopolysaccharide produced by all enterococci, required for normal cell growth,division, resistance to antibiotics and pathogenesis. This enterococcal polysaccharideantigen (EPA) is encoded by two gene clusters: (i) 18 genes extremely conserved (epaA-epaR) encoding a core synthetic machinery and (ii) 10-20 genes variable from one strain toanother, responsible for the decoration of the polysaccharide backbone. We have built amutant with a complete deletion of the epa variable region and shown that the decoration ofEPA (but not its core structure) is essential for the biological activity of this polymer. Wepropose investigate the structural properties of Epa and dissect the specific contribution ofthis polymer and its decoration to bacterial physiology and antibiotic resistance.We will take a multidisciplinary approach to explore EPA structure and to understand howEPA controls the distribution and activity of surface proteins involved in cell wall assemblyand resistance to antibiotics. The project will involve state-of-the-art methodologiesincluding super-resolution microscopy (fluorescence and electron microscopy), structuralglycobiology (NMR, mass spectrometry) and conventional approaches to study bacterialphysiology and antimicrobial resistance. The candidate will work with members of thesupervisors' laboratories studying bacterial cell surface assembly and host-pathogeninteractions.

拟议的项目侧重于所有肠球菌产生的表面hamno多糖的功能分析，肠球菌是正常细胞生长、分裂、抗生素抗性和发病所必需的。这种肠球菌多糖抗原（EPA）由两个基因簇编码：(i) 18个极度保守的基因（epaA-epaR）编码核心合成机制；（ii） 10-20个基因在不同菌株之间变化，负责多糖骨架的修饰。我们构建了epa可变区完全缺失的突变体，并表明fepa的修饰（而不是其核心结构）对该聚合物的生物活性至关重要。我们建议研究Epa的结构特性，剖析这种聚合物及其装饰对细菌生理和抗生素耐药性的具体贡献。我们将采用多学科的方法来探索EPA的结构，并了解EPA如何控制参与细胞壁组装和抗生素耐药性的表面蛋白的分布和活性。该项目将涉及最先进的方法，包括超分辨率显微镜（荧光和电子显微镜），结构糖生物学（核磁共振，质谱）和传统方法来研究细菌生理学和抗菌素耐药性。候选人将与导师实验室的成员一起研究细菌细胞表面组装和宿主-病原体相互作用。