Collaborative Research: Identification of nitrogen sources for toxic Alexandrium blooms using a novel species-specific tracer, d15N-saxitoxin

合作研究：使用新型物种特异性示踪剂 d15N-石房蛤毒素识别有毒亚历山大藻华的氮源

• 批准号: 1505604
• 负责人: Juliette Smith
• 金额: $ 39.44万
• 依托单位: College of William & Mary Virginia Institute of Marine Science
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-15 至 2016-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1505604&HistoricalAwards=false
• 关键词: Collaborative; Research; Identification; nitrogen; sources

The US and other countries throughout the world are affected by harmful algal blooms (HABs) that negatively impact human health, marine ecosystems, fisheries resources, and local economies. Anthropogenic nutrient loadings have been linked to expanding HAB incidence, but the relationship is site- and organism-specific, and is still poorly understood. The main challenge in this regard is to determine the relative importance of natural versus anthropogenic nutrient sources in the development of an individual HAB species. Given the diverse nature of the planktonic assemblage in which HABs occur, and the lack of appropriate measurement techniques, this is exceedingly difficult to accomplish.In this project, research teams at the Woods Hole Oceanographic Institution and University of Texas at Austin will take a novel approach to this challenge: They use use the nitrogen isotopic signature (del15N) of a species-specific HAB toxin to identify the nitrogen source and chemical form that promotes cell growth and toxin production. The bloom-forming dinoflagellate Alexandrium fundyense and its class of bioactive compounds, saxitoxins (STXs), are an ideal model system as STXs are nitrogen-rich and are typically only produced by a single species in mixed plankton assemblages. The guiding overall hypothesis is that the isotopic signature of a HAB-specific toxin can be used to discriminate between anthropogenic and natural sources of N and provide more details than bulk material del15N on the source, chemical form, and processing of N that lead to blooms of a particular toxic species. This hypothesis is based on the principle that human and animal waste in groundwater and sewage become 15N-enriched and inorganic fertilizers 15N-depleted, relative to natural sources of N in catchment waters. While the use of the isotopic ratio del15N of bulk biomass to identify nitrogen sources to coastal waters is a widely accepted practice, this use of a toxin as a species-specific tracer or marker is new and will provide details on the explicit source, chemical form, and processing of nitrogen that results in blooms of a particular HAB species. Broader Impacts: This project addresses fundamental issues underlying the most widespread of all HAB poisoning syndromes, paralytic shellfish poisoning (PSP), a major form of shellfish poisoning that affects countries throughout the world. Project results can also assist in policy decisions about pollution control and other bloom mitigation strategies, and can be applied to a range of HAB species - those that produce saxitoxins, as well as those that produce other toxins that are nitrogen rich. Project results will be broadly disseminated through scientific papers, presentations at workshops, domestic and international conferences, and departmental seminars, and discussions with the media.

美国和世界各地的其他国家都受到有害藻华（HAB）的影响，对人类健康，海洋生态系统，渔业资源和地方经济产生负面影响。人为营养的负荷与扩大的HAB发生率有关，但这种关系是特定于现场和有机体的，并且仍然很了解。这方面的主要挑战是确定自然与人为营养源在单个HAB物种发展中的相对重要性。考虑到HAB发生的浮游木结合组合的多样性以及缺乏适当的测量技术，这是难以完成的。在这个项目中，伍德斯孔海洋学机构和奥斯汀的得克萨斯州的研究团队将采取这种挑战的新方法，他们会使用硝基质量的nitrogen sigenter（del15n）的形式（del15n），并识别物种的形式（del15n）。促进细胞生长和毒素产生。形成鲜花的鞭毛鞭毛盐亚历山大fundyense及其生物活性化合物Saxitoxins（STXS）是理想的模型系统，因为STXS是富含氮的且通常仅由混合浮游生物组合中的单个物种产生的。 指导性的总体假设是，HAB特异性毒素的同位素特异性特异性签名可用于区分n的人为和自然来源，并提供更多的细节，而不是大量的材料DEL15N在源，化学形式和n的加工中，导致特定有毒物种的花朵。该假设基于以下原则：与集水区域中N的自然来源相对于N耗尽15N的人类和污水中的人类和污水中的人类和动物废物。虽然将同位素比例DEL15N的散装生物量DEL15N用于鉴定沿海水域的氮源是一种广泛接受的实践，但这种将毒素作为一种物种特异性的示踪剂或标记的使用是新的，并且将提供有关氮的显着源，化学形式和加工的细节，这些硝基机器人是在特定的Hab of An Blooms中产生的。更广泛的影响：该项目解决了所有HAB中毒综合症，瘫痪贝类中毒（PSP）中最普遍的基本问题，这是影响全世界国家的一种主要形式。项目结果还可以帮助制定有关污染控制和其他鲜花缓解策略的政策决策，并可以应用于一系列HAB物种 - 生产萨克西毒素的物种以及产生其他含氮富含氮的毒素的物种。项目结果将通过科学论文，研讨会，国内和国际会议以及部门研讨会以及与媒体的讨论来广泛传播。