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: 9754762
• 负责人: Kimberley Diane Seed
• 金额: $ 47.03万
• 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/9754762
• 关键词: Antiviral Agents; Area; Bacteriophages; Binding; Cells; Cholera; Chromosomes; Complex; Cytolysis; Data; Development; Disease; Disease Outbreaks; Disease Outcome; Ecosystem; Elements; Ensure; Environment; Epidemic; Epidemiology; Evolution; Gene Cluster; Gene Expression; Genes; Genetic Transcription; Genome; Genomic approach; Goals; Gram-Positive Bacteria; Human; Immunity; Infection; Infection Control; Infrastructure; 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; Resistance; Rupture; Shapes; Specificity; Structural Protein; Structure; System; Testing; Therapeutic; Therapeutic community technique; Vibrio cholerae; Viral; Virulence; Virulence Factors; Work; antimicrobial; base; cytotoxic; cytotoxicity; diarrheal disease; functional genomics; global health; improved; microbial; microbial community; novel; pathogen; pressure; prevent; prophylactic; protein structure; response; transmission process; waterborne pathogen; 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.

霍乱弧菌等水生病原体对全球健康构成重大威胁。霍乱弧菌可持续存在于 它的出现可能在流行地区和其他地区造成毁灭性的霍乱暴发， 基础设施受损、人口流离失所的脆弱地区。主持人- 决定疾病结果和霍乱传播动力学的病原体相互作用发生在 一种复杂的微生物生态系统，包括捕食性细菌病毒（Predatory bacterial viruses，缩写为BBV）。知识分子 噬菌体捕食对流行菌株选择的影响需要加强我们的研究。 了解影响霍乱弧菌进化和流行病学的力量。我们发现一本小说 一组移动的遗传元件称为PLE（噬菌体诱导的染色体岛样元件）是一个关键 霍乱弧菌用来抵御噬菌体攻击的武器。我们的假设是， 有效的、高度特异性的抗病毒屏障，通过两种不同的机制起作用，以确保噬菌体不 传播并扩散到邻近的霍乱弧菌细胞。我们的数据表明，PLEs通过抑制 产生必需的噬菌体蛋白，并在所有子代噬菌体之前破裂感染的细菌细胞 完成其复制周期。为了详细了解PLE活动的机制，我们将继续以下内容 具体目标：1）我们将定义当V. Cholesterol在噬菌体的攻击下，并确定特异性如何被赋予到PL-噬菌体相互作用上。（二） 我们将确定PLE如何干扰噬菌体产生必需蛋白的能力。在这一目标下，我们 将使用功能基因组学方法和突变分析的组合来分离这方面的 来自PLE介导的细胞裂解的PLE活性。3)我们将确定PLE介导的细菌感染的分子基础， 细胞裂解。我们将表征对细胞毒性PLE-coded产物不敏感的抑制子， 了解PLE如何有效地杀死噬菌体感染的霍乱弧菌。拟议的研究将确定如何 噬菌体的捕食作用塑造了流行性霍乱弧菌的基因组。这些知识将增进我们对 噬菌体介导的微生物种群在健康和疾病状态的扰动，并进一步我们的能力， 为了治疗或预防的利益而操纵这些社区。