Defining a Molecular Signature of Uropathogenic Escherichia coli

定义泌尿道致病性大肠杆菌的分子特征

• 批准号: 10390116
• 负责人: Grace Morales
• 金额: $ 3.2万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10390116
• 关键词: Acute; Address; Affect; Anabolism; Area; Bacteremia; Bacteria; Bacterial Infections; Bacteriuria; Bladder; Clinic; Clinical; Code; Collection; Comparative Genomic Analysis; Culture Media; Cystitis; Data; Diagnostic; Diarrheagenic E. coli; Disabled Persons; Elderly; Electronic Health Record; Escherichia coli; Genes; Genetic; Genetic Polymorphism; Genome; Genomic Segment; Genomic approach; Genomics; Goals; Growth; Hypoxanthines; Individual; Infection; Life; Link; Medical Records; Membrane Proteins; Metabolic; Methods; Modeling; Molecular Profiling; Nature; Nucleic Acid Regulatory Sequences; Nucleotides; Operon; Outcome; Pathogenesis; Pathogenicity; Pathway interactions; Patients; Phenotype; Population; Proteins; Proteomics; Purines; Recurrence; Regulation; Reporting; Research; Role; Symptoms; Techniques; Testing; Time; Transcript; Untranslated RNA; Urinary tract; Urinary tract infection; Urine; Uropathogenic E. coli; Variant; Virulence; Woman; Work; bacterial metabolism; biobank; comparative genomics; computational pipelines; diagnostic signature; differential expression; experience; experimental study; extracellular; fitness test; flexibility; genetic signature; genome wide association study; metabolomics; microbial; microbial genome; molecular diagnostics; molecular marker; mouse model; mutant; novel; pan-genome; pathogen; pathogenic bacteria; purine metabolism; recurrent infection; transcriptomics; uptake; urinary

PROJECT SUMMARY Urinary tract infections (UTIs) are among one of the most common bacterial infections, afflicting 50% of women at least once in their lifetime. Approximately 30% of these women will experience a recurrent infection. Escherichia coli is the most common cause and is responsible for 75% of these infections. Bacteria in the urine, bacteriuria, is a spectrum of clinical presentations, ranging from asymptomatic (ASB), to severe symptoms(such as bacteremia). Unlike diarrheagenic E. coli, UPEC do not have a discrete genetic factor to use for diagnostic purposes. This creates a bottleneck in diagnostics when discerning an asymptomatic urocolonizer from a pathogenic isolate. This is particularly challenging for patient groups such as the elderly or disabled who are unable to communicate the presence of symptoms. There is a significant need to identify a diagnostic molecular signature of UPEC. While there is no discrete gene that defines UPEC, we have previously shown a metabolic signature that does differentiate ASB and cystitis isolates. Many of these metabolites are associated with purine metabolism. While it is known that purine biosynthesis is implicated in the pathogenesis of several bacterial pathogens, the role of purine salvage remains largely unknown. The goal of this proposal is to identify a molecular signature for UPEC. To identify potential areas of focus, we first assessed how the nucleotide intermediate, hypoxanthine, is taken up over time. Our preliminary data show ASB isolates uptake hypoxanthine faster than cystitis isolates. The overarching hypothesis of this project is that subtle genomic features dictate the regulation of purine metabolism, constituting a defining and diagnostic genetic signature for UPEC. To test this hypothesis, I will use transcriptomics, proteomics, and computational genomics to assess the potential of purine metabolism as a molecular signature. Experiments in Aim 1 will investigate the roles of hypoxanthine salvage during a UTI in a well-defined murine model. I will explore differences in membrane proteins and transcript abundance of known genes involved in purine metabolism throughout infection, and use targeted comparative genomics to look for variations in the gene operons of these pathways. In Aim 2, I will take a broad, unbiased genomics approach to identify other potential genomic regions that could constitute a molecular signature. I will utilize isolates banked at our microbial biobank, linked to the de-identified medical record, and subject them to sequencing and a genome-wide association study (GWAS). Collectively, these data will provide a rigorous definition of UPEC, while investigating a potential molecular signature. Additionally, these studies will define the role of purine salvage in UPEC pathogenesis. The proposed work will have broad implications in purine metabolism in bacterial pathogenesis as well as the novel use of microbial GWAS with patient- phenotypes.

项目摘要 尿路感染是最常见的细菌感染之一，50%的女性患有尿路感染。 至少一次。这些妇女中约有30%将经历复发性感染。 大肠杆菌是最常见的原因，占这些感染的75%。尿液中的细菌， 菌尿是一系列临床表现，从无症状（ASB）到严重症状（如 如菌血症）。与大肠杆菌E.大肠杆菌，UPEC没有离散的遗传因子用于诊断 目的这在区分无症状的尿定植者与无症状的尿定植者时造成了诊断上的瓶颈。 病原分离物。这对于老年人或残疾人等患者群体尤其具有挑战性， 无法传达症状的存在。存在鉴定诊断分子的显著需要， UPEC的签名。虽然没有定义UPEC的离散基因，但我们先前已经显示了代谢性UPEC。 这是一个区分ASB和膀胱炎分离株的特征。这些代谢物中有许多与嘌呤有关 新陈代谢.虽然已知嘌呤生物合成与几种细菌的发病机制有关， 病原体，嘌呤补救的作用仍然在很大程度上未知。这项提案的目标是确定一种分子 UPEC的签名。为了确定潜在的重点领域，我们首先评估了核苷酸中间体， 次黄嘌呤，随着时间的推移而被吸收。我们的初步数据显示，ASB分离物摄取次黄嘌呤的速度快于 孤立性膀胱炎。这个项目的首要假设是，微妙的基因组特征决定了 嘌呤代谢的调节，构成了UPEC的定义和诊断基因签名。到 为了验证这一假设，我将使用转录组学、蛋白质组学和计算基因组学来评估 嘌呤代谢作为分子标记。目的1中的实验将研究次黄嘌呤的作用 在明确定义的鼠模型中，UTI期间的挽救。我将探索膜蛋白的差异， 在整个感染过程中参与嘌呤代谢的已知基因的转录本丰度，以及靶向使用 比较基因组学来寻找这些途径的基因操纵子的变异。在目标2中，我将采取广泛的， 无偏见的基因组学方法，以确定其他潜在的基因组区域，可能构成一个分子 签名.我将利用微生物生物库中的分离物，与去识别医疗记录相关联， 对它们进行测序和全基因组关联研究（GWAS）。这些数据将提供 UPEC的严格定义，同时研究潜在的分子特征。此外，这些研究将 明确嘌呤补救在UPEC发病机制中的作用。拟议的工作将在以下方面产生广泛影响： 嘌呤代谢在细菌发病机制中的作用以及微生物GWAS在患者中的新用途， 表型