Collaborative Research: Viral induced chemotaxis mediating cross-trophic microbial interactions and carbon flux

合作研究：病毒诱导的趋化性介导跨营养微生物相互作用和碳通量

• 批准号: 1829905
• 负责人: Sheri Floge
• 金额: $ 62.1万
• 依托单位: Wake Forest University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1829905&HistoricalAwards=false
• 关键词: Collaborative; Research; Viral; induced; chemotaxis

Drifting photosynthetic microbes in surface ocean waters carry out nearly half of global carbon (C) fixation, both supporting the marine food web and reducing atmospheric carbon dioxide (CO2) levels. The fate of C in ocean ecosystems is controlled by myriad individual interactions within a highly interconnected planktonic food web, the sheer complexity of which has hindered predictive understanding of global C cycling. Chemical cues govern microbial interactions, and during infection, marine viruses manipulate the metabolism of phytoplankton and bacteria, facilitating the release of dissolved organic matter from infected cells. This research aims to determine how viral metabolic reprogramming of and organic matter release from intact, infected phytoplankton influences microbial interactions and C cycling. The interdisciplinary, collaborative nature of the project will enable direct training of two postdoctoral researchers, one graduate student, and undergraduate students in viral ecology, microfluidics, and metabolomics. An educational outreach program that engages middle school students in hands-on, high speed imaging of microbes will be expanded, and the project will culminate in a three-day workshop to advance the application of microfluidic devices and mass spectrometry analyses in microbial ecology.The overarching hypothesis behind this research is that viral infection alters the chemical landscape of intact, infected picophytoplankton cells, attracting neighboring chemotactic bacteria and protistan zooplankton, and altering C flux pathways. To test this idea, a series of linked multi-scale laboratory-based experiments will be run to 1) Characterize the response of diverse model marine microbes to dissolved organic matter (DOM) released from intact, virus-infected picophytoplankton using microfluidics-based chemotaxis assays, 2) Identify key viral-derived DOM compounds eliciting chemotactic responses using stable isotope labeling, metabolomics analyses, and chemotaxis assays, and 3) Quantify micron-scale cross-trophic encounter dynamics and evaluate their impact on bulk-scale C cycling using liter-scale measurements of C dynamics linked to high spatiotemporal resolution live imaging of microbial food webs. The ultimate goal of the project is to develop a mechanistic understanding of the role of intact, virus-infected cells in oceanic C cycling.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

地表海水中的光合微生物的漂流量持续了几乎一半的全球碳（C）固定，既支持海洋食品网，又降低了大气二氧化碳（CO2）水平。海洋生态系统中C的命运受到高度相互联系的浮游食品网络中各种个人相互作用的控制，其纯粹的复杂性阻碍了人们对全球C循环的预测理解。化学线索控制微生物相互作用，在感染期间，海洋病毒操纵浮游植物和细菌的代谢，促进了从感染细胞中释放出溶解有机物的。这项研究旨在确定有机物和有机物从完整，感染的浮游植物中释放的病毒代谢重编程如何影响微生物相互作用和C循环。该项目的跨学科协作性质将使两名博士后研究人员，一名研究生以及病毒生态学，微流体和代谢组学的本科生进行直接培训。一项教育宣传计划将扩大与中学生的动力，高速成像，该项目将在为期三天趋化细菌和Protistan浮游动物，并改变C通路途径。为了测试这一想法，将运行一系列链接的基于实验室的实验，至1）表征多种模型海洋微生物对从完整的，病毒感染的皮基植物释放出的溶解有机物（DOM）的响应代谢组学分析和趋化测定法，以及3）量化微米尺度的跨营养性相遇动态，并使用与高时空分辨率实时成像的c动力学的升级测量结果评估它们对散装尺度C循环的影响。该项目的最终目的是对完整的，感染病毒感染的细胞在海洋C循环中的作用有一种机械理解。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的评估来评估值得支持的。