Collaborative Research: Vibrio as a model microbe for opportunistic heterotrophic response to Saharan dust deposition events in marine waters

合作研究：弧菌作为模型微生物，对海水中撒哈拉尘埃沉积事件进行机会性异养响应

• 批准号: 1357140
• 负责人: William Landing
• 金额: $ 20.06万
• 依托单位: Florida State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1357140&HistoricalAwards=false
• 关键词: Collaborative; Research; Vibrio; model; microbe

Overview: Dust and mineral aerosols are a significant source of micro and macronutrients to oligotrophic ocean surface waters. Evidence is growing that heterotrophic microbes may play key roles in processing deposited minerals and nutrients. Yet it is not known which components of dust stimulate the heterotrophic bacteria, which cellular mechanisms are responsible for the utilization of those components and how the activity of these bacteria affect the availability and utilization of dust-derived minerals and nutrients by marine autotrophs. Knowledge of these factors is key to understanding how dust deposition impacts carbon cycles and for predicting the response of tropical oceans to future changes in the frequency and intensity of dust deposition events. The objective of this project is to examine the specific effects of aeolian dust on heterotrophic microbes in a tropical marine system under controlled conditions. The central hypothesis is that in oligotrophic tropical systems numerically minor opportunistic bacteria are the first responders to influx of dust constituents and respond primarily by rapidly accessing soluble trace metals and limiting nutrients that are deposited with Saharan dust. The project will focus on two specific aims: 1) Quantify changes in community structure, composition and transcriptional activity among marine microbial populations upon exposure to dust, and 2) Identify key components in Saharan dust aerosols that stimulate or repress growth and/or activity in Vibrio, a model opportunistic marine heterotrophic group. The study will use a series of controlled experiments designed to identify and quantify heterotrophic microbial response to dust deposition events using both natural communities and model bacteria (Vibrio) through metagenomics, transcriptomics and atmospheric and marine biogeochemical techniques. This innovative approach will identify the most critical (reactive) components leached from dust aerosols on the microbial community as well as elucidate potential mechanisms of response.Intellectual Merit: There is great interest in the biological response to dust aerosols given its potentially large influence on biogeochemical cycling, but there has been relatively little work that has addressed the mechanisms of response (especially among the heterotrophic microbial fraction) or identified the relative importance of specific constituents of dust aerosols. A detailed framework for microbial response (focusing on opportunistic heterotrophs) will facilitate efforts to link autotrophic and heterotrophic processing. This contribution is significant because it will provide one of the first end-to-end (chemistry to physiology to ecology) mechanistic pathways for marine biological response to desert dust aerosols.Broader Impacts: The outcomes of this research will provide information on an often overlooked component of climate change, the long range effects of desertification, which could impact biogeochemical cycling throughout the oceans. Furthermore, working with Vibrio as a model will have the co-benefit of addressing the possible role of dust deposition on the global rise of a marine infectious agent. Additionally, this project will provide graduate, undergraduate and high school students with both training and active participation in research. All students will have opportunities to present their work at local and regional meetings as well as national (international) conferences. Through on-going programs at each institution, students from STEM under-represented groups will be recruited for research opportunities (and for entry into graduate programs). Additionally, through participation in the Georgia Coastal Research Council results of this work, and related issues in marine science and climate change, will be broadly disseminated to policy-makers and local (coastal) stakeholders through meetings, links to the GRGC website and listserv and targeted publications.

概述：灰尘和矿物质气溶胶是少亲营海地表水的微营养素的重要来源。有证据表明，异养微生物可能在处理沉积矿物质和营养中起关键作用。然而，尚不清楚粉尘的哪些成分刺激异养细菌，哪些细胞机制负责利用这些成分，以及这些细菌的活性如何影响海洋自养生粉尘衍生的矿物质和营养素的可用性和利用。对这些因素的了解是了解灰尘沉积如何影响碳周期的关键，以及预测热带海洋对尘埃沉积事件频率和强度的未来变化的反应。该项目的目的是检查在受控条件下，在热带海洋系统中，风化粉尘对异养微生物的特定影响。中心假设是，在贫营养的热带系统中，数值较小的机会细菌是对粉尘成分涌入的第一批响应者，主要是通过迅速获取可溶性痕量金属和限制撒哈拉粉尘沉积的养分。该项目将侧重于两个具体的目的：1）量化海洋微生物种群中社区结构的变化，组成和转录活动的变化，并在暴露于灰尘时量化，2）识别撒哈拉粉尘气溶胶中的关键组成部分，这些尘埃剂刺激或抑制颤动中的生长和/或活性，这是一个模型的传染性杂质亲子群。该研究将使用一系列旨在通过元基因组学，转录组学和大气和海洋生物地球化学技术来识别和量化异养微生物对尘埃沉积事件的反应和量化杂物性沉积事件的反应。这种创新的方法将确定从微生物群落上的灰尘气溶胶中浸出的最关键的（反应性）组成部分，并阐明了反应的潜在机制。智能优点：对生物学气溶胶对生物地球化学循环的潜在影响的影响很大，但相对较少的工作却与之相对较少，这与肉体相对较少的响应（相对较少的机构）相对尤其如此，而这是相对较少的响应（尤其是烦恼的），这是相对较少的响应（尤其是烦恼）。或确定了尘埃气溶胶特定成分的相对重要性。微生物反应的详细框架（专注于机会性异构性）将有助于努力将自养和异养的处理联系起来。 This contribution is significant because it will provide one of the first end-to-end (chemistry to physiology to ecology) mechanistic pathways for marine biological response to desert dust aerosols.Broader Impacts: The outcomes of this research will provide information on an often overlooked component of climate change, the long range effects of desertification, which could impact biogeochemical cycling throughout the oceans.此外，与Vibrio一起作为模型的合作将具有解决尘埃沉积在海洋传染剂全球崛起中可能作用的共同利益。此外，该项目将为毕业生，本科和高中生提供培训和积极参与研究。所有学生将有机会在当地和区域会议以及国家（国际）会议上介绍他们的工作。通过每个机构的持续计划，将招募来自STEM不足的小组的学生以供研究机会（并进入研究生课程）。此外，通过参与佐治亚州沿海研究委员会的成果以及海洋科学和气候变化的相关问题，将通过会议，链接到GRGC网站和列表服务和目标出版物，将其广泛传播给政策制定者和地方（沿海）利益相关者。