MIP: Abundance, Dynamics, and Diversity of Viruses in the Northwestern Sargasso Sea

病毒是海洋群落中无处不在的、丰富的和动态的组成部分。大多数海洋病毒是噬菌体(感染细菌的病毒)。病毒影响全球碳循环和营养循环，调节海洋细菌群落的组成，并在水平基因转移中发挥重要作用。最近的研究揭示了海洋中病毒的巨大多样性；然而，大多数对病毒多样性的深入研究都集中在单个样本上，即在空间和时间上的快照。由于细菌和病毒群落在性质上是动态的(快速感染、产生、腐烂)，多样性的快照不足以描述海洋系统的微生物生态。该项目将在两年的时间里研究位于马尾藻海西北部的S水电站深度剖面上病毒的丰度、多样性和动态。每月将通过直接显微镜计数确定病毒丰度和深度，并将使用分子方法(脉冲场凝胶电泳法、针对微阵列的杂交和特定噬菌体基因的聚合酶链式反应)监测病毒群落组成的变化。将使用该地点现有的微生物和生物地球化学数据进行多变量分析，以确定哪些参数与病毒丰度和群落组成的变化有关。将确定病毒的产生和衰减率，以及病毒对细菌群落的影响。最后，该项目将研究海洋单链DNA微噬菌体的生态，这是一种新描述的病毒群，在马尾藻海中发现大量存在。该项目的目标是产生一个关于该地点病毒群落的空间和时间变化的综合数据集，并确定病毒丰度和多样性是否存在反复(从而可预测)的模式。该项目具有重要的科学意义，因为病毒在海洋生态系统的生物地球化学循环和基因转移中发挥着关键作用。尽管海洋病毒群落的丰富性和重要性，但其多样性和动态还没有得到很好的了解。该项目的数据将结合海洋微生物观测站和百慕大大西洋时间序列研究测量的参数进行分析。这将成功地将时间序列的范围扩大到包括病毒，并提供了一个可以分析病毒数据趋势的背景。将通过向公共数据库发布数据和建立一个网站，详细介绍病毒采样技术和来自西北部马尾藻海的结果来传播数据。这笔助学金将用于培养一名研究生和三名本科生。还将通过将病毒生态学部分纳入百慕大海洋科学研究所每年开设的夏季微生物海洋学课程，对研究生和本科生进行培训。K-12年级的学生将通过为女童子军(11-14岁)创建海洋微生物学补丁计划参与其中，参与者将在其中学习微生物学、影响海洋及其内部生物学的问题，以及可能的海洋科学家职业选择。

Viruses are ubiquitous, abundant, and dynamic components of marine communities. The majority of marine viruses are phage (viruses that infect bacteria). Viruses influence global carbon and nutrient cycles, regulate the composition of marine bacterial communities, and play a major role in horizontal gene transfer. Recent studies have revealed an enormous diversity of viruses in the oceans; however, most in-depth studies of viral diversity have focused on a single sample a snapshot in space and time. Since bacterial and viral communities are dynamic in nature (rapid infection, production, decay), snapshots of diversity are inadequate for describing the microbial ecology of marine systems. This project will examine the abundance, diversity, and dynamics of viruses over a depth profile at Hydrostation S in the northwestern Sargasso Sea during a two-year period. Viral abundance with depth will be determined monthly by direct microscopic counts, and changes in the composition of the viral community will be monitored using molecular methods (pulsed-field gel electrophoresis, hybridization against microarrays, and PCR for specific phage genes). Multivariate analyses will be performed using available microbial and biogeochemical data from this site to determine which parameters correlate with changes in viral abundance and community composition. Rates of virus production and decay, as well as the impact of viruses on the bacterial community, will be determined. Finally, this project will examine the ecology of the marine single-stranded DNA Microphage, a newly described viral group found to be abundant in the Sargasso Sea. The goal of this project is to produce a comprehensive dataset on the spatial and temporal variation of the viral community at this site and determine if there are recurring (and thus predictable) patterns in viral abundance and diversity. This project is of scientific importance because of the critical roles viruses play in biogeochemical cycling and gene transfer in marine ecosystems. Despite their abundance and importance, the diversity and dynamics of marine viral communities are not well-understood. The data from this project will be analyzed in conjunction with the parameters measured by the Oceanic Microbial Observatory and the Bermuda Atlantic Time-series Study. This will successfully expand the scope of the time series to include viruses and provide a context in which trends in the viral data can be analyzed. Data will be disseminated through release into public databases and the creation of a website with details of viral sampling techniques and results from the northwestern Sargasso Sea. This grant will support the training of one graduate student and three undergraduate students. Graduate and undergraduate students will also be trained through the integration of a viral ecology segment into the summer Microbial Oceanography course offered annually at the Bermuda Institute of Ocean Sciences. K-12 students will be involved through the creation of a Marine Microbiology patch program for Cadette Girl Scouts (ages 11-14), where participants will learn about microbiology, issues affecting the oceans and the biology within it, and possible career options as a marine scientist.