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

病毒无处不在，数量丰富，是海洋群落的动态组成部分。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。最近的研究表明，海洋中的病毒种类繁多；然而，大多数对病毒多样性的深入研究都集中在空间和时间上的单个样本上。由于细菌和病毒群落在本质上是动态的（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。该项目将在为期两年的时间内，在马尾藻海西北部S站的深度剖面上研究病毒的丰度、多样性和动态。每月通过直接显微镜计数确定病毒深度丰度，并使用分子方法（脉冲场凝胶电泳、微阵列杂交和特异性噬菌体基因PCR）监测病毒群落组成的变化。将利用该站点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相关。将确定病毒产生和衰变的速度，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微噬细胞的生态学，这是一种新发现的病毒群，在马尾藻海中大量存在。该项目的目标是建立一个关于该站点病毒群落时空变化的综合数据集，并确定病毒丰度和多样性是否存在重复出现（因此可预测）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。尽管它们丰富而重要，但海洋病毒群落的多样性和动态尚未得到很好的了解。该项目的数据将与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一起进行分析。这将成功地扩展时间序列的范围，使其包括病毒，并提供可以分析病毒数据趋势的上下文。数据将通过向公共数据库发布和建立一个网站来传播，该网站详细介绍了病毒取样技术和西北马尾藻海的结果。这项资助将用于培养一名研究生和三名本科生。研究生和本科生也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提供的夏季微生物海洋学课程来接受培训。K-12学生将参与为Cadette女童子军（11-14岁）创建的海洋微生物补丁计划，参与者将学习微生物学，影响海洋的问题及其生物学，以及作为海洋科学家的可能职业选择。

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.