Expansion of enterococcal insertion sequence elements during bacteriophage infection

噬菌体感染期间肠球菌插入序列元件的扩展

• 批准号: 10665579
• 负责人: Joshua M Kirsch
• 金额: $ 3.55万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-10 至 2025-09-09
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10665579
• 关键词: Acceleration; Adsorption; Ampicillin; Antibiotic Resistance; Bacteria; Bacterial Genome; Bacteriophages; Cellular biology; Clinic; Complex; DNA Insertion Elements; DNA Transposable Elements; Data; Elements; Enterococcus; Enterococcus faecalis; Environment; Evolution; Family; Frequencies; Future; Gene Activation; Gene Expression; Genes; Genetic; Genetic Transcription; Genome; Goals; Gram-Positive Bacteria; Human; IS Elements; Infection; Kinetics; Knowledge; Laboratories; Life Style; Location; Lytic; Mediating; Methodology; Mobile Genetic Elements; Multi-Drug Resistance; Outcome; Pharmaceutical Preparations; Phenotype; Physiological; Predatory Behavior; Process; Public Health; Resistance; Risk; Series; Sigma Factor; System; Testing; Therapeutic; Therapeutic Uses; Time; Transcript; Translations; Transposase; Vancomycin; Virulence; Virus; Work; alternative treatment; clinical phenotype; clinically relevant; experimental study; fitness; genetic makeup; genetic manipulation; genome sequencing; genome-wide; insight; next generation sequencing; novel; opportunistic pathogen; pathogen; pressure; promoter; resistance mechanism; response; trait; transcription factor; whole genome

PROJECT SUMMARY Multidrug resistant enterococcal infections are a serious public health threat. The enterococci, including Enterococcus faecalis, often harbor resistance to critical front-line drugs such as ampicillin and/or vancomycin. Due to the increasing difficulty of treating enterococcal infections with currently available drugs, alternative treatment options are needed. One possibility is the therapeutic use of bacterial viruses known as bacteriophages (phages). While phage therapy has shown promise in the clinic, the emergence of phage resistance in bacteria is a serious concern for future phage therapies. To overcome this, we need to understand how bacteria respond to phage infection at the genetic level and the physiological consequences of phage resistance. Past work in our lab discovered that E. faecalis isolates resistant to lytic phage 19 (phi19) infection harbored an increased number of IS256 transposable element insertions in their genomes. These insertions were commonly found in genes involved in phage infection, suggesting that phi19 infection stimulates IS256 transposition to create new genetic combinations, leading to phage resistance. My preliminary work has demonstrated that phi19 infection activates IS256 mobilization. I have found that phi19 infection increases the translation of the IS256 transposase, and that a phi19-encoded transcription factor that resembles an anti-sigma factor, termed PAS19, increases IS256 transposase translation. This indicates that PAS19 is responsible for activating IS256 during phi19 infection. The goals of this project are to decipher how the E. faecalis genome evolves in response to phage driven IS256 activation, and how these downstream effects can inform phage therapeutic strategies. To achieve these goals, I will execute two specific aims: Aim 1: Establish a mechanistic basis for phage-induced expansion of IS256 insertions in E. faecalis. Work performed in this aim will demonstrate the functional enzymatic requirements and timing of phage mediated IS256 activation, and will determine if this activity is broadly applicable to diverse enterococcal phages; Aim 2: Determine how a putative phage transcription factor controls IS256 activation. PAS19, a putative transcription factor encoded by phi19 activates IS256 expression. In this aim, I will delineate how PAS19 controls IS256 gene activation.

项目摘要 抗多药的肠球菌感染是严重的公共卫生威胁。肠球菌，包括 肠球菌粪便通常具有对关键前线药物（例如氨苄西林和/或万古霉素）的抵抗力。 由于用当前可用的药物治疗肠球菌感染的难度越来越大 需要治疗选择。一种可能性是将细菌病毒的治疗用途称为 噬菌体（噬菌体）。虽然噬菌体疗法在诊所表现出希望，但噬菌体的出现 细菌的耐药性是对未来噬菌体疗法的严重关注。为了克服这一点，我们需要 了解细菌如何应对遗传水平的噬菌体感染和生理后果 噬菌体抗性。我们实验室中的过去工作发现，粪肠球菌分离出对裂解噬菌体19（phi19）的抗性 感染具有增加其基因组中IS256转座元件插入的数量。这些 插入通常在参与噬菌体感染的基因中发现，表明PHI19感染 刺激IS256换位以创建新的遗传组合，从而导致噬菌体抗性。我的 初步工作表明，PHI19感染激活IS256动员。我发现Phi19 感染增加了IS256转座酶的翻译，并且是PHI19编码的转录因子 类似于称为PAS19的抗sigma因子增加IS256转座酶翻译。这表明 PAS19负责在PHI19感染期间激活IS256。该项目的目标是破译如何 粪肠球菌基因组随着噬菌体驱动的IS256激活以及这些如何下游而演变 效果可以为噬菌体治疗策略提供信息。为了实现这些目标，我将执行两个具体目标：目标 1：建立噬菌体诱导的IS256插入大肠杆菌插入的机械基础。工作 在此目的中执行将证明噬菌体介导的功能性酶促要求和时间安排 IS256激活，并将确定此活动是否广泛适用于各种肠球菌噬菌体；目标2： 确定推定的噬菌体转录因子如何控制IS256激活。 Pas19，一个推定的 通过PHI19编码的转录因子激活IS256表达。在这个目标中，我将描述如何PAS19 控制IS256基因激活。