Molecular Probes for Nutrient Stress in Phytoplankton: Emiliania Huxleyi as a Model

浮游植物营养胁迫的分子探针：Emiliania Huxleyi 作为模型

• 批准号: 9818543
• 负责人: Brian Palenik
• 金额: $ 17万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至 2003-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9818543&HistoricalAwards=false
• 关键词: Molecular; Probes; Nutrient; Stress; Phytoplankton

Palenik 9818543Molecular Probes for Nutrient Stress in Phytoplankton: Emiliania huxleyi as a model.Numerous examples exist where both the type and physiological status of the phytoplankton influence major processes in the oceans such as carbon fixation, calcification, sulfur gas emission, and toxic bloom formation. Our ability to understand the physiological status in the field of individual phytoplankton species or individual cells is limited, however. Most biological field measurements (carbon fixation, C:N ratio, Fv/Fm, for example) currently integrate over the whole phytoplankton community. In the long term, an understanding of the physiological ecology of individual "keystone" phytoplankton species will provide a more mechanistic, predictive understanding of ecosystem processes.Emiliania huxleyi is an abundant, cosmopolitan phytoplankton species which is important in the global biogeochemical cycles of carbon and sulfur because of its production in the water column of calcite (coccoliths) and the sulfur gas DMS. It is present in both oligotrophic and neritic environments and in some locations is known to form massive blooms visible in satellite images. To date our understanding of the ecology of this organism has focused on these bloom phenomena.One of the research goals of the field of phytoplankton ecology is the development of incubation-independent probes of phytoplankton nutrient status. From previous work an antibody to a cell surface protein, NRP1, that is present in nitrogen-stressed, but not nitrate--replete or ammonia-replete E. huxley has been developed. In this study the antibody will be used to develop a field method for characterizing the physiological state of natural E. huxleyi populations. A whole cell assay will be optimized and its efficiency and sensitivity characterized for examining cell numbers down to those present in oligotrophic environments. Fluorescence microscopy and image analysis will be used to quantify the number of cells expressing NRP1 and ideally the relative level of expression.An antibody to intact whole cells will be developed to count the total and percent nitrogen-stressed cells in samples. A few previously obtained samples from the California current and the coast of Norway will be tested initially for the presence of nitrogen-stressed cells in the field. The demonstration of the physiological state of a specific phytoplankton group would be novel. This work will involve the training of one graduate student and one or more undergraduates in emerging techniques for applying immunological probes to marine ecological questions.

PALENIK 9818543浮游植物中营养应激的分子探针：艾米利亚尼亚Huxleyi作为模型。存在浮游植物的类型和生理状态，影响碳固定，钙化，硫化，硫化气体排放和毒性鲜明和毒性的含量和生理状态。但是，我们了解单个浮游植物物种或单个细胞领域的生理状况的能力受到限制。大多数生物场测量（例如，碳固定，C：N比，FV/FM）当前在整个浮游植物社区中整合。 In the long term, an understanding of the physiological ecology of individual "keystone" phytoplankton species will provide a more mechanistic, predictive understanding of ecosystem processes.Emiliania huxleyi is an abundant, cosmopolitan phytoplankton species which is important in the global biogeochemical cycles of carbon and sulfur because of its production in the water column of calcite (coccoliths) and the sulfur煤气DMS。它存在于贫营养环境和neritic环境中，在某些位置，它在卫星图像中形成可见的大量盛开。迄今为止，我们对这种生物的生态学的理解一直集中在这些布鲁姆现象上。从以前的工作中，已经开发了一种抗体到细胞表面蛋白NRP1，它存在于氮气胁迫（但不是硝酸盐）中的抗体 - 已开发了E. Huxley。在这项研究中，抗体将用于开发一种表征天然E. huxleyi种群生理状态的现场方法。全细胞测定法将得到优化，其效率和灵敏度用于检查细胞数量，以归结为贫营养环境中的细胞数量。荧光显微镜和图像分析将用于量化表达NRP1的细胞数量，理想情况下，将开发完整整体细胞的抗体，以计算样品中氮气压力的总和百分比。先前从加利福尼亚电流和挪威海岸获得的一些样品最初将测试该领域中存在氮气压力细胞。特定浮游植物群体的生理状态的演示将是新颖的。这项工作将涉及对一名研究生和一名或多名本科生的培训，以将免疫学探针应用于海洋生态问题。