POPULATION GENETICS AND GENOME EVOLUTION OF VIRUSES IN AN AQUATIC ENVIRONMENT

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 噬菌体是细菌间水平基因交换的重要通道，与许多细菌病原体的毒力直接相关。噬菌体编码的毒力因子包括致病菌株中的志贺毒素和霍乱弧菌中的霍乱毒素。噬菌体可以通过毒力因子的水平转移来驱动新的致病菌株的出现，因此了解噬菌体基因组的进化具有重要的公共卫生意义。这项研究项目将研究噬菌体的种群遗传学和基因组进化。我们将检验这一假设，即噬菌体种群和群落中的大部分遗传多样性可以归因于最近噬菌体之间以及噬菌体与细菌之间的水平基因交换事件。一个自然的水生噬菌体群落将被用来解决关于噬菌体基因组进化和水生噬菌体种群和群落内水平基因转移的频率的问题。本研究的具体目的是：(1)评估水平基因转移事件的频率及其对噬菌体基因组组织和进化的影响；(2)检测特定噬菌体的群体遗传学/基因组学以确定同一种群中的噬菌体携带横向转移的宿主衍生基因的不同等位基因的程度；(3)分析噬菌体基因组中携带的非病毒、非宿主遗传物质的组成和分布；以及(4)培训本科生在生物医学研究中使用的关键分子遗传学技术。学生将在完成个人项目时获得科学交流、实验室技术、仪器使用和生物信息学方面的经验。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Bacteriophages are important conduits for horizontal gene exchange among bacteria and are directly responsible for the virulence of many bacterial pathogens. Phage-encoded virulence factors include the shiga toxins in pathogenic strains of Escherichia coli and the cholera toxin in Vibrio cholerae. Bacteriophages can drive the emergence of new pathogenic bacterial strains through the horizontal transfer of virulence factors and thus an understanding of phage genome evolution has important public health implications. This research project will examine the population genetics and genome evolution of bacteriophages. We will test the hypothesis that much of the genetic diversity within bacteriophage populations and communities can be attributed to recent horizontal genetic exchange events among phages and between phages and bacteria. A natural community of aquatic bacteriophages will be used to address questions about phage genome evolution and the frequency of horizontal gene transfer within populations and communities of aquatic bacteriophages. The specific aims of this research are to: (1) Assess the frequency of horizontal gene transfer events and its influences on bacteriophage genome organization and evolution, (2) Examine the population genetics/genomics of specific bacteriophages to determine the extent to which bacteriophages in the same population carry different alleles of laterally transferred host-derived genes, (3) Analyze the composition and distribution of non-viral, non-host genetic material carried in bacteriophage genomes, and (4) Train undergraduate students in the key molecular genetic techniques used in biomedical research. Students will gain experience in scientific communication, laboratory techniques, use of instrumentation, and bioinformatics as they complete individual projects.