OCE-PRF Track 1 (Broadening Participation): Cryptic Sulfonate Cycling between Marine Phytoplankton and Heterotrophic Bacterioplankton

化学物质和能量形式的信息不断地在海洋微生物的复杂网络中流动。在表层海洋中，阳光和大气中的二氧化碳被自养的单细胞浮游植物捕获，并转化为一个巨大的有机物池，微生物将其用作新陈代谢货币和信号分子，形成不同贸易联盟的基础。几种鲜为人知的磺酸盐化合物最近被确定为海洋细菌-浮游植物相互作用的关键货币，似乎在沿海社区普遍存在。在这个项目中，该研究员将调查磺酸盐在海洋微生物相互作用中的普遍性和作用，以及它们对地球生物地球化学的影响。在华盛顿大学E·弗吉尼亚·阿姆布鲁斯特博士的赞助下，该研究员将通过微生物生态学和海洋生物地球化学方面的跨学科培训，在专业上取得进步。扩大参与范围的活动包括指导一名本科生，并为当地一所为少数族裔服务的高中制定一个外联计划，在该计划中，学生将利用微生物学和生物信息学的概念进行课堂实验室练习。磺酸盐分别由几种重要的浮游植物和异养细菌产生和降解。然而，这些化合物代表了海洋有机物质池中一个鲜为人知的组成部分。在某种程度上，磺酸盐提供了一种无法量化的碳和硫通量，支持细菌和浮游植物之间的相互作用，在某种程度上，磺酸盐代表着海洋中碳和硫转化中神秘的缺失环节。在这项研究中，该研究员将使用基于实验室的方法来研究模式浮游植物中对磺酸盐产生的生理和生态控制，以及基于现场的方法来研究普吉特湾沿海水域和北太平洋周围水域磺酸盐池的分类驱动的动态。具体地说，该研究员将对产生磺酸盐的浮游植物类群进行代谢概况分析(目标一)，并分别利用有针对性的现场代谢物调查(二)和稳定同位素培养(三)，以及基于转录学的确定控制磺酸盐衍生碳的命运的海洋微生物(四)，测量海洋环境中磺酸盐的时空梯度和周转率。计划中的实验将首次深入描述环境中磺酸盐对海洋有机质池的贡献、分类驱动的时空动力学以及它们在海洋生态系统相互依存中的作用。

Information in the form of chemicals and energy flows constantly through complex networks of marine microbes. In the surface ocean, sunlight and atmospheric carbon dioxide are captured by autotrophic unicellular phytoplankton and transformed into a vast pool of organic matter that microbes use as metabolic currencies and signaling molecules to form the basis for different trading alliances. Several little-known sulfonate compounds have recently been identified as key currencies underlying marine bacterial-phytoplankton mutualisms and appear to be widespread in coastal communities. In this project, the fellow will investigate the prevalence and role of sulfonates in marine microbial interactions and their resulting impact on the Earth's biogeochemistry. With sponsor Dr. E. Virginia Armbrust at the University of Washington, the fellow will advance professionally through interdisciplinary training in microbial ecology and marine biogeochemistry. Broadening participation activities include mentorship of an undergraduate and development of an outreach program for a local minority-serving high school where students will conduct classroom laboratory exercises using microbiological and bioinformatics concepts. Sulfonates are produced and degraded by several important phytoplankton and heterotrophic bacterial taxa, respectively. Yet, these compounds represent a poorly understood component of the marine organic matter pool. To the extent that sulfonates account for an unquantified flux of carbon and sulfur that supports mutualisms between bacteria and phytoplankton, sulfonates represent cryptic missing links in both carbon and sulfur transformations in the ocean. In this study, the fellow will use laboratory-based approaches to examine physiological and ecological controls on sulfonate production in model phytoplankton species and field-based approaches to examine taxonomically driven dynamics of sulfonate pools in the coastal waters of Puget Sound and surrounding North Pacific. Specifically, the fellow will perform metabolic profiling of model sulfonate-producing phytoplankton taxa (Aim I) and measure spatiotemporal gradients and turnover rates of sulfonates in the ocean environment using targeted in situ metabolite surveys (II) and stable isotope incubations (III), respectively, together with transcriptomics-based identification of marine microbes that control the fate of sulfonate-derived carbon (IV). The planned experiments will provide the first intensive characterization of sulfonates in the environment in terms of their contribution to the marine organic matter pool, their taxonomically driven spatiotemporal dynamics, and their roles in ocean ecosystem interdependencies.