OCE-PRF Track 1 (Broadening Participation): Impact of Phytoplankton-Bacteria Interactions on Metal Bioavailability

OCE-PRF 第 1 轨道（扩大参与范围）：浮游植物-细菌相互作用对金属生物利用度的影响

• 批准号: 1421196
• 金额: $ 17.4万
• 依托单位: Gauglitz Julia
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1421196&HistoricalAwards=false
• 关键词: OCE; PRF; Track; Broadening; Participation

In this two year postdoctoral research fellowship, the fellow will analyze how bacteria-picophytoplankton interactions impact the utilization of trace metals from desert dust. Results of these experiments will elucidate biological advantages conferred by the production of metal chelators, as it reveals the role that bacteria play in phytoplankton metal acquisition, and will advance understanding in oceanic primary production and carbon cycling. The fellow will broaden participation of under-represented groups in ocean sciences at local high schools and diversity-serving colleges through teaching modules and research internships focusing on the ocean sciences and marine trace metal nutrition. The fellow is being hosted by sponsoring scientist Dr. Mak Saito at Woods Hole Oceanographic Institution.The research examines how the interactions between bacteria and phytoplankton modulate the bioavailability of metals from desert dust, and thus impact metal uptake and the growth of phytoplankton. The work addresses the following hypothesis: The presence of bacteria in picophytoplankton cultures will (a) enable iron and cobalt solubilization, (b) spur picophytoplankton metal uptake and growth, and (c) lead to expression of iron uptake transporters which more closely resembles their expression in the natural marine environment. Specifically, the picoeukaryote Ostreococcus and the cyanobacterium Crocosphaera will be grown in semi-continuous cultures under axenic conditions (control), with bacterial isolates (laboratory culture experiments) and in the presence of natural bacterial populations (shipboard culture experiments), with and without addition of desert dust, under trace metal clean conditions. Ostreococcus and Crocosphaera are representative model organisms for processes of picoeukaryotic photosynthesis and nitrogen fixation. Treatment effects on growth rate, metal uptake, and ligand conditional stability constants will be measured. Siderophore transporters and other proteins involved in iron uptake will be detected by proteomic methods. Further, a differential and quantitative proteomic approach will allow for the detection of proteins involved in iron uptake in subsurface ocean samples, in order to compare to the transporters and transporter expression levels of experimental cultures.

在这两年的博士后研究奖学金中，该研究员将分析细菌 - 斑型粉状浮游生物的相互作用如何影响沙漠灰尘中的痕量金属的利用。这些实验的结果将阐明金属螯合剂的生产所赋予的生物学优势，因为它揭示了细菌在浮游植物金属获取中的作用，并将促进海洋初级生产和碳循环的理解。该研究员将通过教授关注海洋科学和海洋痕量金属营养的教学模块和研究实习，扩大当地高中和多样性服务学院海洋科学和多样性服务学院的参与。该研究员由赞助科学家Mak Saito博士在Woods Hole Oceanographic机构主持。该研究研究了细菌与浮游植物之间的相互作用如何调节沙漠灰尘中金属的生物利用度，从而影响金属吸收和浮游植物的生长。这项工作解决了以下假设：皮皮托粉培养物中的细菌存在将（a）启用铁和钴溶解化，（b）刺激性皮层浮游生物金属摄取和生长，以及（c）导致铁摄取蛋白的表达，从在自然海洋环境中的表达。具体而言，Picoeukaryote ostreococococcus和Cyanobacterium crocosphaera将在半连续培养物中生长在半连续培养物（对照）（对照），细菌分离株（实验室培养实验）（实验室培养实验），并且在没有天然细菌种群（船舶培养实验）的情况下，并在没有添加的情况下进行。沙漠灰尘，在痕量金属清洁条件下。 Ostreocococcus和Crocosphaera是用于Picoeukaryotic光合作用和氮固定过程的代表性模型生物。将测量对生长速率，金属摄取和配体有条件稳定性常数的治疗效果。蛋白质组学方法将检测到铁载体转运蛋白和其他参与铁摄取的蛋白质。此外，差异和定量蛋白质组学方法将允许检测地下海洋样品中与铁摄取的蛋白质，以便与实验培养物的转运蛋白和转运蛋白表达水平进行比较。