Adenosine triphosphate as a master variable for biomass in the oceanographic context

三磷酸腺苷作为海洋学背景下生物量的主变量

• 批准号: 2319114
• 负责人: Alexander Bochdansky
• 金额: $ 47.06万
• 依托单位: Old Dominion University Research Foundation
• 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: 2023-08-15 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2319114&HistoricalAwards=false
• 关键词: Adenosine; triphosphate; master; variable; biomass

In the ocean, most living organisms are microbes that are too small to be seen by the naked eye. Despite their small size, microbes play an important role in processes that govern marine ecosystems and food webs. For example, microbes affect the concentrations of nutrients and gases in the water and the atmosphere, thereby exerting a significant impact on the climate globally. Consequently, it is important to know how many microbes there are in any given environment because there is a direct causal connection between living mass and overall biological activity. Determining how “alive” any volume of water is, however, is a difficult task. The gold standard is to count microbial cells under the microscope. This method is extremely time consuming when done well and needs to be performed separately on many different types of microbial cells. In addition, standard microscopic techniques do not reveal whether the cells were alive when they were collected. In contrast, a chemical method based on the amount of adenosine triphosphate (ATP) offers distinct advantages. Notably, ATP is relatively easy to measure, and the method can be widely used because all living cells contain ATP in similar concentrations. This study tests and applies an improved method of ATP analysis to generate data at very high resolution in space and time. One PhD student and six undergraduate students will receive research training and the project fosters international research collaborations with European scientists. This research provides deeper insights into the distribution of live matter in different regions and depths of the world’s oceans. Decades ago, adenosine triphosphate (ATP) was proposed as a universal biomass indicator. However, its application in the field of oceanography has been limited due to misconceptions regarding cellular ATP concentration. Recent evidence suggests that ATP functions as a hydrotrope requiring homeostatically controlled ATP levels much higher than those solely needed for energy metabolism. ATP occurs in surprisingly stable concentrations in cytoplasm across a wide range of microbes thus representing live cytoplasm volume. This project examines in detail the usefulness of particulate ATP (PATP) as a biomass marker over a large section of the North Atlantic Ocean with special emphasis on mesopelagic and deep-sea environments where chlorophyll is a poor indicator of biomass or associated biological processes. The project uses field collections of marine snow and ambient water in combination with particle cameras to examine the microscale heterogeny of biomass in the water column. Laboratory studies determine factors that may influence the recovery of PATP through filtration and extraction protocols and determine to what extent ATP concentrations potentially deviate from the typical cytoplasm concentration during phosphorus limitation. The improved PATP-biomass method offers numerous operational advantages, especially the fact that it can be employed at high spatial and temporal resolution. Once validated, the PATP biomass method could be widely adopted as a key variable for biomass in routine oceanographic surveys. This project supports graduate and undergraduate students from diverse backgrounds to contribute to laboratory and field research. Public outreach efforts include tours and presentations for middle and high-school students, as well as the general public.This project is funded by the Chemical Oceanography and Biological Oceanography Programs in the Division of Ocean Sciences.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.

在海洋中，大多数活生物体都是微生物，它们太小而无法被肉眼看到。尽管尺寸很小，但微生物在控制海洋生态系统和食物网的过程中起着重要作用。例如，微生物会影响水和大气中的养分和气体的浓度，从而对全球气候产生重大影响。因此，重要的是要知道在任何给定环境中有多少微生物，因为生物质量与整体生物学活动之间存在直接的灾难性联系。但是，确定“活着”的任何水是一项艰巨的任务。金标准是在显微镜下计算微生物细胞。做得很好，此方法非常耗时，需要在许多不同类型的微生物细胞上分别执行。此外，标准的微观技术不会揭示细胞收集时是否还活着。相比之下，一种基于三磷酸腺苷（ATP）量的化学方法提供了不同的优势。值得注意的是，ATP相对易于测量，并且该方法可以广泛使用，因为所有活细胞都包含相似浓度的ATP。这项研究测试并应用了改进的ATP分析方法，以在时空分辨率很高的情况下生成数据。一名博士生和六名本科生将接受研究培训，该项目促进了与欧洲科学家的国际研究合作。这项研究提供了对世界海洋不同地区和深度的现场物质分布的更深入的见解。几十年前，提出了三磷酸腺苷（ATP）作为通用生物质指标。然而，由于细胞ATP浓度的失误，它在海洋学领域的应用受到限制。最近的证据表明，ATP充当需要体内稳态控制的ATP水平的氢气，远高于能量代谢所需的ATP水平。 ATP以惊人的稳定浓度发生在细胞质中，遍布广泛的微生物，从而代表活细胞质体积。该项目详细介绍了特定ATP（PATP）作为北大西洋大部分地区的生物量标记物的有用性，并特别强调了叶绿素叶绿素是生物量或相关生物学过程的较差指标。该项目将海洋雪和环境水的现场收集与粒子摄像机结合使用，以检查水柱中生物量的微观异质发育。实验室研究确定可能通过过滤和提取方案影响PATP恢复的因素，并确定在磷限制期间，ATP浓度可能偏离典型的细胞质浓度的程度。改进的PATP-BIOMASS方法具有许多操作优势，尤其是可以在高空间和临时分辨率下使用的事实。一旦验证，PATP生物量方法可以被广泛用作常规海洋学调查中生物质的关键变量。该项目支持来自潜水员背景的毕业生和本科生，为实验室和现场研究做出贡献。公众推广工作包括为中学和高中生以及公众的演讲和演讲。该项目由海洋科学部的化学海洋学和生物海洋学计划资助。该奖项反映了NSF的法定任务，并被认为是通过评估基金会的知识和更广泛的影响来通过评估来获得支持的珍贵。