Targeted and comparative viral community genomics of the Eastern North Pacific

北太平洋东部地区的目标和比较病毒群落基因组学

• 批准号: 0961947
• 负责人: Matthew Sullivan
• 金额: $ 57.67万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2014-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0961947&HistoricalAwards=false
• 关键词: Targeted; comparative; viral; community; genomics

Two climatically and biogeochemically important features characterize the Eastern North Pacific (ENP). This region encompasses one of the planet's largest oxygen minimum zones, and annually hosts a phytoplankton bloom that leads to some of the highest dimethyl sulfide (DMS) concentrations observed. Oxygen minimum zones (OMZs) play integral roles in marine biogeochemical cycles, as major sinks for nitrogen and sources for climatologically active trace gases including methane and nitrous oxide. There is increasing evidence that projected ocean warming and circulation changes is decreasing dissolved oxygen concentrations within the coastal and interior regions of the ENP, causing lateral and vertical OMZ expansion. This will have a direct effect on coastal benthic ecosystems and the productivity of marine fisheries, as well as potentially positive climatalogical feedbacks. In addition, the DMS produced in the ENP is a potential negative feedback for atmospheric warming through its role in atmospheric cloud formation, while it also accounts for approximately half of the planet's total biogenic sulfur flux. The PI of this project has collaborated with Dr. Steven Hallam (UBC) since June 2008 to archive viral community DNA, paired with high molecular weight genomic DNA from microbial biomass (since June 2006) and a rich synoptic oceanographic metadataset, along defined redox gradients in the ENP as part of the Canadian-funded Line P time series program. The viral samples focus on open-ocean station OSP and span surface waters, hypoxic interior, and upper and lower oxichypoxic transition zones. Microbial investigations, ongoing since 2006, have examined community diversity and population structure of indigenous microbial groups in the ENP. Time-series analyses have revealed dynamic seasonal changes, consistent with changing light, temperature, and nutrient conditions. However, little is known about the role that co-occurring viral communities play in modulating microbial community dynamics and responses to both water column hypoxia and massive DMS production and sulfur cycling. Marine viruses are responsible for the largest flux of carbon in the oceans by lysing microbial cells, while also encoding "host" metabolic genes. In the case of marine cyanobacteria, phage directly impact global carbon cycling by encoding ~60% of the core reaction center genes in surface water photosystems. Understanding coupled viral, microbiological and biogeochemical processes the ENP is critical to understand, predict, or one day possibly mitigate changes in productivity and trace gas cycling associated with OMZ expansion and changing DMS production. This project will investigate viral community diversity and metabolic capacity through viral metagenomes sampled along defined spatiotemporal gradients in the ENP. The endeavor is highly leveraged with funding already secured for sequencing 20 viral metagenomes, and their co-occurring microbial communities at high phylogenetic resolution using 16S hypervariable sequence tagging through the DOE JGI Community Sequencing Program and the Moore Foundation viral sequencing initiative. This project will identify relevant patterns of viral-host interaction with profound ecological and evolutionary consequences.Broader impacts: The microbial and viral sampling effort will be performed by post-docs and graduate students in the context of a 50+ year oceanographic sampling effort that allows these trainees see the vast biogeochemical and physical oceanographic measurements required to "survey" an ocean community. This project will expose undergraduates and high school students to the excitement of field-based oceanographic research through a combination of direct involvement in research, a Biosphere 2 "hands-on sampling training", and a new course at Tucson High School entitled "Ocean viruses: From isolates to genomes and metagenomes".

两个在气候和生物地球化学上重要的特征是北太平洋东部（ENP）的特征。该区域包括该行星最大的最小氧气区域之一，并每年托管浮游植物开花，导致观察到的一些最高的二甲基硫化物（DMS）浓度。氧最小区域（OMZ）在海洋生物地球化学周期中起着不可或缺的作用，作为氮的主要水槽和气候活性痕量气体（包括甲烷和一二氮氧化物）的源。越来越多的证据表明，预计的海洋变暖和循环变化正在降低ENP沿海和内部区域内溶解的氧气浓度，从而导致侧向和垂直OMZ膨胀。这将直接影响沿海底栖生态系统和海洋渔业的生产力，以及潜在的积极的气候反馈。此外，在ENP中产生的DMS是通过大气云中的作用进行大气变暖的潜在负反馈，而它也约占该行星总生物硫的一半。 自2008年6月以来，该项目的PI与Steven Hallam博士（UBC）合作，与Microbial Biomass的高分子量基因组DNA（自2006年6月以来）和丰富的Synoptic Oceanogrich Metadataset搭配，并沿着ENP的一部分Canadian Fime Seremens Seregram配对。病毒样品专注于开放海洋站OSP和跨越地表水，低氧内部以及上和下氧化过渡区。 自2006年以来一直进行的微生物研究检查了ENP中土著微生物群体的社区多样性和人口结构。时间序列分析显示了动态的季节性变化，与光，温度和养分条件的变化一致。然而，对同时发生的病毒群落在调节微生物群落动力学以及对水柱缺氧和大量DMS产生和硫循环中的反应中所发挥的作用知之甚少。海洋病毒是通过裂解微生物细胞来导致海洋中最大的碳通量，同时还编码“宿主”代谢基因。在海洋蓝细菌的情况下，噬菌体通过在地表水光系统中编码约60％的核心反应中心基因直接影响全局碳循环。了解耦合的病毒，微生物和生物地球化学过程ENP对于理解，预测或有一天可能会减轻与OMZ扩展和DMS生产变化相关的生产率变化和痕量气体循环的变化至关重要。 该项目将通过ENP中定义的时空梯度采样的病毒宏基因组研究病毒群落的多样性和代谢能力。 这项努力高度利用了已经获得的资金来测序20个病毒宏基因组，并且使用DOE JGI社区测序程序和Moore Moore基础基础依据的启动性使用16S高变量序列标记，它们在高系统发育分辨率下以高系统发育分辨率进行了良好的资金。 该项目将确定病毒式互动的相关模式，并具有深远的生态和进化后果。BRODER的影响：在50岁以上的海洋学抽样工作的背景下，生态和病毒采样工作将由研究生和研究生进行，使这些受训者可以看到这些庞大的生物地球化学和物理测量结果测量对海洋社区的调查。该项目将通过直接参与研究，生物圈2“动手抽样培训”以及图森高中的新课程，题为“海洋病毒：从分离株到基因组和基因瘤”，将使本科生和高中生对基于现场的海洋学研究的兴奋”。