Understanding the role of Ngo1049 in subverting host-mediated metal starvation in Neisseria gonorrhoeae

摘要 淋病奈瑟菌(Ngo)是一种引起性传播的人类专性细菌病原体。 感染性淋病。由于淋病发病率的增加和抗生素耐药性的增加，疫苗和新的 迫切需要治疗药物。一种有希望的战略是瞄准营养金属获取系统，因为它们 通常是保守的，在感染期间表达，对细菌在体内的生存是必不可少的。非政府组织破坏 通过表达外膜转运蛋白获得必需金属的宿主金属限制机制 人类金属隔离蛋白，如钙保护素和银屑病蛋白中的锌，乳铁蛋白和乳铁蛋白中的铁 转铁蛋白。然而，许多支持Ngo在金属限制条件下生长的基因产品仍然存在 没有特征的。我们发现，ngo1049基因的产物在锌胁迫下生长的Ngo中高表达。 限制条件。Ngo1049在致病奈瑟氏菌中保守，生物信息学分析预测 Ngo1049是一种定位于周质的金属结合转移酶。上游发现了一个Zur结合基序 Ngo1049的表达受Zur(锌吸收调节因子)的调控，Zur抑制了ngo1049的表达。 锌浓度高。Ngo1049转录本在人类宫颈上皮细胞感染过程中高度诱导 细胞，提示Ngo1049在NGO发病机制中可能起重要作用。基于这些发现，我假设 Ngo1049是一种受Zur调控的蛋白质，在金属受限的条件下，在炎症中促进锌的获取 上皮面。为了检验这一假设，在这份F31-多样性提交书中，我建议确定 Ngo1049的本地化与调控机制(S)。其次，我将研究Ngo1049对锌的贡献 在金属限制条件下的获取。最后，我将定义Ngo1049如何使NGO在炎症中存活 接触含有金属螯合蛋白的上皮细胞和人类免疫细胞后的粘膜表面。 通过定义Ngo金属调节子的这个新成员，我的工作可能会指出这一点的新疗法 耐抗生素细菌。通过将细菌生理学和遗传学、生物化学和 细胞微生物学，以及我在毕业期间获得的职业发展机会 培训，这个项目将为我提供追求职业生涯的背景和专业知识 寄主-病原体相互作用的学术研究实验室。

Abstract Neisseria gonorrhoeae (Ngo) is an obligate human bacterial pathogen that causes the sexually transmitted infection gonorrhea. Due to increasing rates of gonorrhea and increased antibiotic resistance, vaccines and new therapeutics are urgently needed. A promising strategy is targeting nutrient metal acquisition systems since they are usually conserved, expressed during infection, and essential for bacterial survival in vivo. Ngo undermines host metal restriction mechanisms by expressing outer membrane transporters to acquire essential metals from human metal-sequestering proteins such zinc from calprotectin and psoriasin and iron from lactoferrin and transferrin. However, many gene products that support Ngo growth in metal-limiting conditions remain uncharacterized. We found that the product of the ngo1049 gene is highly expressed in Ngo grown under zinc- limiting conditions. Ngo1049 is conserved among pathogenic Neisseria, and bioinformatic analysis predicts that Ngo1049 is a metal-binding transferase localized in the periplasm. A Zur binding motif was identified upstream of ngo1049, suggesting expression is regulated by Zur (zinc uptake regulator), which represses expression in high zinc concentrations. ngo1049 transcripts are highly induced during Ngo infection of human endocervical cells, indicating a potential role for Ngo1049 in Ngo pathogenesis. Based on these findings, I hypothesize Ngo1049 is a Zur-regulated protein that facilitates zinc acquisition in metal-limited conditions at inflamed epithelial surfaces. To test this hypothesis, in this F31-Diversity submission I propose to determine the localization and regulation mechanism(s) of Ngo1049. Second, I will examine the contribution of Ngo1049 to zinc acquisition in metal-limiting conditions. Lastly, I will define how Ngo1049 enables Ngo survival at inflamed mucosal surfaces after exposure to epithelial cells and human immune cells that contain metal chelating proteins. By defining this new member of the Ngo metal regulon, my work will potentially point to new therapies for this antibiotic-resistant bacterium. Through its combination of bacterial physiology and genetics, biochemistry, and cellular microbiology, as well as the professional development opportunities available to me during my graduate training, this project will provide me with the background and expertise to pursue a career as the leader of an academic research laboratory in host-pathogen interactions.