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: 2245249
• 负责人: Solange Duhamel
• 金额: $ 42.16万
• 依托单位: University of Arizona
• 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=2245249&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) 是所有生命形式所需的重要营养素。 在维持全球一半光合作用和氧气供应的海洋中，磷的稀缺足以限制生物生产力、二氧化碳吸收，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。这种不平衡可能会增加海洋生态系统中磷的压力水平，使海洋生产力越来越受到磷供应的控制。鉴于磷在维持现在和未来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归宿。在这个项目中，研究小组研究了海洋多磷酸盐（polyP），这是一种普遍存在但人们对所有生物体产生的磷形式知之甚少的形式。为了弥补海洋多聚体的主要知识空白，研究人员正在克服主要技术障碍，首次对海洋微生物中多聚体进行定量测量。这些测量是在实验室微生物培养物以及来自高磷供应环境（例如加利福尼亚海流生态系统）或非常低磷供应（例如地中海）的环境中的现场样本中进行的。此外，研究小组正在解析海洋多聚磷在这些不同生物体和环境中的细胞功能，以阐明其在生物磷营养中的作用。这项工作有助于推进多学科跨学科研究，包括陆地科学甚至癌症研究，并在磷生物修复方面有广泛的应用。该项目支持两名女科学家实验室的一名博士后研究员、一名研究生和几名本科生。通过该项目正在制作和传播向公众介绍海洋息肉的新教育工具。一名 K12 教师正在参与这项工作，并向课堂和网上广大受众传达研究结果。PolyP 在海洋系统中无处不在，在微生物磷营养以及磷矿物质形成和封存中发挥着关键作用。通过这些方式，聚磷有可能影响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。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多聚体库、其链长和生物起源的定量了解。此外，鉴于聚磷作为磷存储分子的观点，最近的观察表明颗粒聚磷在低磷酸盐（Pi）环境中优先保留，这引发了有关其生态生理功能的新问题。为了弥补这些知识差距，解决了两个研究问题： Q1：不同微生物群和环境条件下的聚多糖总含量和链长分布是多少？问题 2：颗粒状聚磷的生产如何在广泛的磷可用性范围内促进微生物磷需求和化学计量？测试了以下假设： H1 (Q1)：功能和环境多样化的浮游生物产生广泛的多聚磷链长度和浓度。 H2 (Q2)：通过分类学和生理学因素的组合，聚磷在低 Pi 环境中的优先保留与其作为储磷分子的作用相协调。这些假设在实验室中使用海洋浮游生物的代表性培养物进行了测试，并在现场使用沿着太平洋和地中海自然 Pi 梯度的观测方法进行了测试。该团队应用一种新的质谱分析 P 靶向方法，解决了海洋多聚磷含量和形态方面前所未有的细节问题。通过将细胞分选与元素、生化和放射性示踪剂分析相结合，该团队对 PolyP 生理学及其在海洋中的循环有了机械性的了解。该项目得到了生物海洋学和化学海洋学计划的支持。该奖项反映了 NSF 的法定使命和通过使用基金会的智力优点和更广泛的影响审查标准进行评估，该项目被认为值得支持。