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

基本信息

批准号：
1829827
负责人：
Jeffrey Guasto
金额：
$ 34.92万
依托单位：
Tufts 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 2022-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1829827&HistoricalAwards=false
关键词：
Collaborative Research Viral induced chemotaxis

项目摘要

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.

表层海水中漂流的光合微生物承担了全球近一半的碳 (C) 固定，既支持海洋食物网，又减少了大气中二氧化碳 (CO2) 的水平。海洋生态系统中碳的命运是由高度互联的浮游食物网内无数个体相互作用控制的，其复杂性阻碍了对全球碳循环的预测性理解。化学信号控制微生物的相互作用，在感染过程中，海洋病毒操纵浮游植物和细菌的新陈代谢，促进受感染细胞释放溶解的有机物。本研究旨在确定完整受感染浮游植物的病毒代谢重编程和有机物释放如何影响微生物相互作用和碳循环。该项目的跨学科、协作性质将使两名博士后研究人员、一名研究生和本科生能够在病毒生态学、微流体学和代谢组学方面进行直接培训。将扩大一项让中学生参与微生物高速成像实践的教育推广计划，该项目将在为期三天的研讨会中达到高潮，以推进微流体装置和质谱分析在微生物生态学中的应用。这项研究背后的总体假设是，病毒感染改变了完整的、受感染的超微型浮游植物细胞的化学景观，吸引邻近的趋化细菌和原生浮游动物，并改变 C 通量路径。为了测试这一想法，将进行一系列相互关联的多规模实验室实验，以：1) 使用基于微流体的趋化性来表征不同模型海洋微生物对完整的、病毒感染的超微型浮游植物释放的溶解有机物 (DOM) 的反应2) 使用稳定同位素标记、代谢组学分析和趋化性测定来鉴定引起趋化反应的关键病毒衍生 DOM 化合物，以及 3)利用与微生物食物网高时空分辨率实时成像相关的升级 C 动态测量，量化微米级跨营养相遇动态，并评估其对大规模 C 循环的影响。该项目的最终目标是对完整的病毒感染细胞在海洋 C 循环中的作用有一个机械的理解。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优势和更广泛的影响进行评估，被认为值得支持审查标准。