High Resolution Linkages Between DOC Turnover and Bacterioplankton in a Coastal Ocean

关于沿海海洋中溶解有机碳(DOC)命运的长期问题需要更好地了解将浮游细菌新陈代谢与碳转化联系起来的网络。这些问题涉及海洋边缘转化的生物活性DOC组分组成的不确定性，以及细菌分类和遗传组成在决定DOC命运中的作用。智力价值该项目将为基于高分辨率化学分析和细菌基因表达测量的沿海碳循环研究注入一种新型数据。它将把DOC过程研究扩展到单化合物水平，将细菌活性研究扩展到单基因水平，并将这些信息整合到现有的生物信息资源中，用于生物地球化学和建模应用。该项目的具体目标是：1)重建连接DOC组成、DOC周转和沿海海洋细菌异养的网络的主要组成部分(DOC池的组成、主要生物活性成分、介导转化的浮游细菌类群以及负责的细菌基因和途径)。2)使用针对复杂的天然微生物群落查询单个DOC化合物的简化系统来测试选定DOC化合物的假设网络链接。3)使用一个简化的系统来测试海洋细菌的假设网络链接，该系统针对复杂的天然DOC池查询单个通用型异养细菌。4)验证预测的DOC-基因链接，这些链接对浮游细菌的异养活性具有最大的信息量。因此，这些将溶解有机碳的化学变化与沿海浮游细菌群落的基因表达模式联系起来的研究将引起几个学科的科学家的兴趣。该项目将培训佐治亚大学海洋科学、微生物学、化学和生态学系的研究生和博士后助理，并为本科生提供研究机会和指导。学生将获得微生物生态学、碳生物地球化学、海洋化学和生物信息学方面的跨学科培训。一项外展计划将为几批有前途的高中生加强对海洋微生物生态作用的理解。每年夏天，PIS将与佐治亚州雅典一所种族多元化的高中的一名高级选修生物学教师合作，开发实验室练习，以实现修改后的AP生物学课程的体验式学习目标。练习将围绕每个高中生从佐治亚州沿海海水中分离出的细菌菌株进行设计，PI将在学年期间合作测试和评估实验室练习。教育期刊和网站上的出版物将使这些练习广泛可用。

Long-standing questions regarding the fate of dissolved organic carbon (DOC) in coastal oceans require a better understanding of the network that links bacterioplankton metabolism with carbon transformation. These questions address uncertainties about the composition of the bioreactive DOC components transformed in ocean margins, and the role of bacterial taxonomic and genetic composition in determining the fate of DOC.Intellectual MeritThis project will infuse a new type of data into coastal carbon cycle research based on high-resolution chemical analysis coupled with bacterial gene expression measures. It will extend DOC process studies down to the single-compound level and bacterial activity studies down to the single-gene level, and integrate this information into existing bioinformatic resources for biogeochemical and modeling applications.The specific goals of the project are: 1) To reconstruct major components of the network linking DOC composition, DOC turnover, and bacterial heterotrophy in the coastal ocean (the composition of the DOC pool, the major bioreactive components, the bacterioplankton taxa mediating transformations, and the bacterial genes and pathways responsible). 2) To test hypothesized network links for selected DOC compounds using a simplified system that queries individual DOC compounds against a complex natural microbial community. 3) To test hypothesized network links for marine bacteria using a simplified system that queries a single generalist heterotrophic bacteria against a complex natural DOC pool. 4) To verify predicted DOC-gene linkages that are most informative about heterotrophic activities of bacterioplankton.Broader ImpactsThis research addresses fundamental questions on bacterial mediation of organic carbon fate in the ocean and atmosphere. As such, these investigations linking the chemical changes in dissolved organic carbon with patterns of gene expression in coastal bacterioplankton communities will be of interest to scientists across several disciplines. The project will train graduate students and postdoctoral associates in the departments of Marine Sciences, Microbiology, Chemistry, and Ecology at the University of Georgia, and provide research opportunities and mentoring for undergraduate students. Students will obtain interdisciplinary training in microbial ecology, carbon biogeochemistry, marine chemistry, and bioinformatics.An outreach program will enhance understanding of the ecological roles of marine microorganisms for several cohorts of promising high school students. PIs will collaborate each summer with an Advanced Placement Biology teacher at a racially diverse Athens, GA, high school to develop laboratory exercises that accomplish experiential learning goals of the revamped AP Biology curriculum. Exercises will be designed around bacterial strains isolated by each high school student from coastal Georgia seawater, and PIs will collaborate in the testing and evaluation of the laboratory exercises during the school year. Publications in educational journals and web sites will make the exercises widely available.