Collaborative Research: Assessing the role of polyphosphate production and cycling in marine ecosystem functioning.

合作研究：评估聚磷酸盐生产和循环在海洋生态系统功能中的作用。

• 批准号: 2245248
• 负责人: Julia Diaz
• 金额: $ 37.82万
• 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: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2245248&HistoricalAwards=false
• 关键词: Collaborative; Research; Assessing; role; polyphosphate

Phosphorus (P) is a vital nutrient required by all forms of life. In the ocean, which sustains half of global photosynthesis and oxygen supply, P can be scarce enough to constrain biological productivity, carbon dioxide uptake, and therefore climate. Human activity is accelerating the delivery of nutrients like P to the ocean, but rates of nitrogen inputs are even greater. This imbalance may increase levels of P stress in marine ecosystems, placing ocean productivity more and more under the control of P supply. Given the critical role of P in sustaining ocean health and ecosystem services now and into the future, a comprehensive understanding of its utilization and fate in the marine environment is necessary. In this project, the research team investigates marine polyphosphate (polyP), a ubiquitous yet poorly understood form of P made by all living organisms. To close major knowledge gaps on marine polyP, the investigators are overcoming major technical barriers to produce the first quantitative measurements of polyP in marine microorganisms. These measurements are being conducted on laboratory microbial cultures, as well as field samples from environments with high P supply, such as the California Current Ecosystem, or very low P supply, such as the Mediterranean Sea. In addition, the research team is resolving the cellular function of marine polyP across these different organisms and environments in order to clarify its role in biological P nutrition. This work helps advance polyP research across disciplines, including terrestrial science and even cancer research, and has broad application to P bioremediation. This project supports a postdoctoral researcher, a graduate student, and several undergraduate students in the labs of two female scientists. New educational tools to teach the public about marine polyP are being produced and disseminated through this project. A K12 teacher is participating in the work and communicating the findings to their classrooms and to broad audiences online.PolyP is ubiquitous in marine systems, where it plays critical roles in microbial P nutrition and P mineral formation and sequestration. In these ways, polyP has the potential to shape long- and short-term marine P cycling, primary productivity, microbial ecology, and global climate. However, major knowledge gaps still exist. Due to technical limitations, the scientific community currently lacks a quantitative understanding of marine polyP pools, their chain lengths, and biological origins. Furthermore, given the view of polyP as a P storage molecule, recent observations pointing to the preferential retention of particulate polyP in low phosphate (Pi) environments raise new questions about its ecophysiological functions. To close these knowledge gaps, two research questions are addressed: Q1: What is the total content and chain length distribution of polyP across different microbial groups and environmental conditions? Q2: How do the production of particulate polyP contribute to microbial P demand and stoichiometry across a broad range in Pi availability? The following hypotheses are tested: H1 (Q1): Functionally and environmentally diverse plankton produce a broad range of polyP chain lengths and concentrations. H2 (Q2): The preferential retention of polyP in low Pi environments can be reconciled with its role as a P storage molecule by a combination of taxonomic and physiological factors. These hypotheses are tested in the laboratory using representative cultures of marine plankton and in the field using observational approaches along natural Pi gradients in the Pacific Ocean and Mediterranean Sea. Applying a new P-targeted method using mass spectrometry, the team is resolving an unprecedented level of detail in marine polyP content and speciation. By combining cell sorting with elemental, biochemical, and radiotracer analyses, the team is gaining a mechanistic understanding of polyP physiology and its cycling in the ocean.This project is supported by the Biological Oceanography and Chemical Oceanography Programs.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

磷(P)是所有生命形式都需要的重要营养物质。在海洋中，维持着全球一半的光合作用和氧气供应，磷的稀缺足以限制生物生产力、二氧化碳的吸收，从而限制气候。人类活动正在加速向海洋输送磷等营养物质，但氮的输入速度甚至更快。这种不平衡可能增加海洋生态系统的磷胁迫水平，使海洋生产力越来越多地受到磷供应的控制。鉴于磷在现在和未来维持海洋健康和生态系统服务方面的关键作用，有必要全面了解其在海洋环境中的利用和命运。在这个项目中，研究小组调查了海洋多磷酸盐（polyP），这是一种普遍存在但鲜为人知的P形式，由所有生物产生。为了缩小海洋息肉的主要知识差距，研究人员正在克服主要的技术障碍，首次对海洋微生物中的息肉进行定量测量。这些测量是在实验室微生物培养以及来自高磷供应环境（如加利福尼亚洋流生态系统）或极低磷供应环境（如地中海）的现场样本上进行的。此外，研究小组正在解决海洋息肉在这些不同生物和环境中的细胞功能，以阐明其在生物P营养中的作用。这项工作有助于推动包括陆地科学甚至癌症研究在内的跨学科息肉研究，并在P生物修复方面具有广泛的应用。本项目资助两名女科学家实验室的一名博士后、一名研究生和几名本科生。透过这个计划，我们制作和分发新的教育工具，教导市民认识海洋珊瑚虫。一名K12教师参与了这项工作，并将调查结果传达给他们的教室和网上的广大观众。水螅藻在海洋系统中普遍存在，它在微生物磷营养和磷矿物形成和封存中起着关键作用。在这些方面，水螅体具有塑造长期和短期海洋磷循环、初级生产力、微生物生态和全球气候的潜力。然而，主要的知识差距仍然存在。由于技术限制，科学界目前缺乏对海洋珊瑚虫池、其链长度和生物起源的定量了解。此外，鉴于息肉P作为P储存分子的观点，最近的观察表明，颗粒息肉P在低磷酸盐（Pi）环境中优先保留，这对其生态生理功能提出了新的问题。为了缩小这些知识差距，解决了两个研究问题：Q1：在不同微生物群和环境条件下，息肉的总含量和链长分布是多少？问题2：在大范围的磷利用率中，微粒息肉P的产生如何影响微生物对磷的需求和化学计量？以下假设被检验：H1 (Q1)：功能和环境多样化的浮游生物产生广泛的水螅链长度和浓度。H2 (Q2)：息肉P在低磷环境中的优先保留可以通过分类和生理因素的组合来协调其作为P储存分子的作用。这些假设在实验室中使用具有代表性的海洋浮游生物培养物进行了检验，并在太平洋和地中海沿自然Pi梯度进行了实地观测。应用一种新的p靶向质谱方法，该团队正在解决海洋息肉p含量和物种形成的前所未有的细节水平。通过将细胞分选与元素分析、生化分析和放射性示踪分析相结合，研究小组对水螅生理及其在海洋中的循环有了更深入的了解。本项目由生物海洋学和化学海洋学计划资助。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。