Phage resistance and mobile genetic elements in Vibrio cholerae

霍乱弧菌的噬菌体抗性和移动遗传元件

• 批准号: 9360091
• 负责人: Kimberley Diane Seed
• 金额: $ 43.06万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-27 至 2021-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9360091
• 关键词: Antiviral Agents; Area; Bacteriophages; Binding; Cells; Cholera; Chromosomes; Complex; Cytolysis; Data; Development; Disease; Disease Outbreaks; Disease Outcome; Ecosystem; Elements; Employee Strikes; Ensure; Environment; Epidemic; Epidemiology; Evolution; Gene Cluster; Gene Expression; Genes; Genetic Transcription; Genome; Genomic approach; Goals; Gram-Positive Bacteria; Human; Immunity; Infection; Infection Control; Intestines; Island; Knowledge; Lipopolysaccharides; Maintenance; Measures; Mediating; Mobile Genetic Elements; Molecular; Mutation; Mutation Analysis; O Antigens; Pathogenicity Island; Phage Receptors; Population; Predatory Behavior; Production; Proteins; Public Health; Recombinants; Reporter; Repression; Research Infrastructure; Resistance; Rupture; Shapes; Specificity; Structural Protein; Structure; System; Testing; Therapeutic; Therapeutic community technique; Vibrio cholerae; Viral; Virulence; Virulence Factors; Work; antimicrobial; base; cytotoxic; cytotoxicity; functional genomics; global health; improved; killings; microbial; microbial community; novel; pathogen; pressure; prevent; prophylactic; response; transmission process; waterborne; weapons

Waterborne pathogens like Vibrio cholerae pose significant threats to global health. V. cholerae can persist in the aquatic environment, and it can emerge to cause devastating cholera outbreaks in endemic regions and in vulnerable areas where infrastructure has been compromised and populations have been displaced. The host- pathogen interactions that dictate disease outcome and cholera transmission dynamics occur in the context of a complex microbial ecosystem that includes predatory bacterial viruses (phages). Knowledge of the molecular consequences of phage predation on the selection of epidemic strains is needed to enhance our understanding of the forces impacting the evolution and epidemiology of V. cholerae. We found that a novel group of mobile genetic elements called PLEs (phage-inducible chromosomal island-like elements) are a key weapon that epidemic V. cholerae uses to protect against phage attack. Our hypothesis is that PLEs are potent, highly specific, antiviral barriers that act through two distinct mechanisms to ensure that phage do not propagate and spread to neighboring V. cholerae cells. Our data indicate that PLEs act by inhibiting the production of essential phage proteins and by rupturing the infected bacterial cell before all progeny phage complete their replication cycle. To understand PLE activity in mechanistic detail we will pursue the following specific aims: 1) We will define the regulatory network that permits the rapid stimulation of PLE activity when V. cholerae is under attack by phage and determine how specificity is imparted onto PLE-phage interactions. 2) We will determine how PLE interferes with the ability of phage to produce essential proteins. Under this aim we will use a combination of functional genomic approaches and mutational analyses to separate this aspect of PLE activity from PLE-mediated cell lysis. 3) We will determine the molecular basis for PLE-mediated bacterial cell lysis. We will characterize suppressors that are insensitive to cytotoxic PLE-encoded products to understand how PLE efficiently kills phage-infected V. cholerae. The proposed studies will establish how phage predation shapes the genome of epidemic V. cholerae. This knowledge will enhance our understanding of phage-mediated perturbations to microbial populations in healthy and diseased states, and further our ability to manipulate these communities for therapeutic or prophylactic benefit.

水传播病原体，例如弧菌霍乱，对全球健康构成了重大威胁。 V.霍乱可以持续 水生环境，它可能会出现在地方性地区和在 基础设施已被妥协并流离失所的脆弱区域。主人- 决定疾病结果和霍乱传播动态的病原体相互作用发生在 一个复杂的微生物生态系统，包括掠食性细菌病毒（噬菌体）。分子知识 需要噬菌体捕食对选择流行病的后果来增强我们 了解影响V.霍乱的进化和流行病学的力量。我们发现这是一本小说 一组称为PLE（噬菌体诱导染色体岛状元素）的移动遗传元素是关键 流行病霍乱的武器用来防止噬菌体攻击。我们的假设是PLES是 通过两种不同的机制起作用的有效，高度特异性的抗病毒屏障，以确保噬菌体不会 传播并扩散到相邻的V.霍乱细胞。我们的数据表明，PLE通过抑制 产生必需的噬菌体蛋白，并在所有后代噬菌体之前破坏感染的细菌细胞 完成其复制周期。要了解机械细节的PLE活动，我们将追求以下 具体目的：1）我们将定义允许在V时快速刺激PLE活性的调控网络。 霍乱受到噬菌体的攻击，并确定如何将特异性赋予ple-phage-phage的相互作用。 2） 我们将确定PLE如何干扰噬菌体产生必需蛋白质的能力。在这个目标下我们 将使用功能基因组方法和突变分析的组合来分开 PLE介导的细胞裂解中的PLE活性。 3）我们将确定PLE介导的细菌的分子基础 细胞裂解。我们将表征对细胞毒性PLE编码产品不敏感的抑制剂 了解如何有效杀死噬菌体感染的V.霍乱。拟议的研究将确定如何 噬菌体捕食塑造了流行病的基因组。这些知识将增强我们的理解 噬菌体介导的对健康和患病状态中微生物种群的扰动，进一步进一步 为了治疗或预防性益处来操纵这些社区。