The Metabolic Response of Coastal Bacteria to Mortality-Derived Phytoplankton Dissolved Organic Matter

沿海细菌对死亡浮游植物溶解有机物的代谢反应

基本信息

批准号：
1634016
负责人：
Elizabeth Kujawinski
金额：
$ 82.73万
依托单位：
Woods Hole Oceanographic Institution
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2016
资助国家：
美国
起止时间：
2016-09-01 至 2021-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1634016&HistoricalAwards=false
关键词：
Metabolic Response Coastal Bacteria Mortality

项目摘要

Microbes interact with one another through the exchange of chemicals dissolved in their surrounding waters. Decades of biochemical research have identified a small suite of chemicals that are required by microbes for growth and well-being. This limited suite is now being expanded with novel analytical tools based on mass spectrometry. In this project, the focus will be on chemicals that are released during the death of microbes, with particular attention paid to burst cells after viral infections and to the remnants of cells after grazing by protozoa (single celled organisms). These chemicals are not intentionally released by their producers, but they can still affect the growth and well-being of nearby bacteria and in turn the bacteria's ability to convert these molecules to carbon dioxide. The proposed comparison of the types and reactivities of chemicals released during the death of a brown tide alga will help improve models of carbon cycling in the coastal ocean. Two graduate students will be supported directly by this project. The proponent plans to teach two classes, one a mass spectrometry course, the other an environmental metabolomics course. It is anticipated that as part of the evolution of the metabolomics course, data-training for metabolomics would become part of the course. Microbial consortia are exquisitely sensitive to chemical changes in their surroundings and the diversity of microbial communities evolves with the composition of available growth substrates and nutrients. Thus, interactions between microbes, through the milieu of dissolved organic matter (DOM), lie at the heart of the global carbon cycle and thus merit significant study and investigation. This project focuses on the molecules that are released during microbial mortality through viral lysis or protozoan grazing. Using novel mass spectrometry-based tools, this project links the composition of dissolved organic matter derived from microbial mortality with the ability of heterotrophic bacteria to remineralize these substrates. Metabolic parameters and carbon transformation rates will be determined as a function of DOM source to assess the impact of DOM type on microbial physiology and carbon turnover. Laboratory results from model organisms will be compared to field settings where the model organisms dominate planktonic communities. The project will generate a suite of molecules that can be used in future experiments as markers of microbial mortality and will provide quantitative comparisons between the reactivity of viral lysate and grazer-derived DOM. These results will support improved parameterizations of microbial networks and their impact on the global carbon cycle.

微生物通过交换溶解在其周围水域中的化学物质相互作用。数十年的生化研究已经确定了微生物需要生长和福祉所需的一小群化学物质。现在，该有限的套件正在使用基于质谱的新分析工具扩展。在该项目中，重点将放在微生物死亡期间释放的化学物质上，特别注意病毒感染后的爆发细胞和原生动物放牧后细胞的残留物（单细胞生物体）。这些化学物质不是由其生产者故意释放的，但它们仍然可以影响附近细菌的生长和福祉，进而将细菌转化为二氧化碳的能力。拟议的比较棕色潮汐藻类死亡期间释放的化学物质的类型和重复性将有助于改善沿海海洋中碳循环的模型。该项目将直接支持两名研究生。拥护者计划教两个课程，一个是质谱课程，另一个是环境代谢组学课程。可以预料，作为代谢组学课程发展的一部分，代谢组学的数据培训将成为该课程的一部分。微生物联盟对周围的化学变化非常敏感，而微生物群落的多样性随着可用的生长底物和养分的组成而发展。因此，微生物之间通过溶解有机物（DOM）的环境之间的相互作用位于全球碳循环的核心，因此值得大量研究和研究。该项目的重点是通过病毒裂解或原生动物放牧期间微生物死亡率释放的分子。该项目使用新型的基于质谱的工具将源自微生物死亡率衍生的溶解有机物的组成与异养细菌回忆这些底物的能力联系起来。代谢参数和碳转化速率将是DOM来源的函数，以评估DOM类型对微生物生理和碳转换的影响。模型生物的实验室结果将与模型生物体主导浮游群落的现场环境进行比较。该项目将产生一组分子，这些分子可以在将来的实验中用作微生物死亡率的标志，并将在病毒裂解物和格拉泽衍生的DOM的反应性之间进行定量比较。这些结果将支持改善微生物网络的参数化及其对全球碳周期的影响。