Collaborative Research: Applying a novel approach to link microbial growth efficiency, function and energy transfer in the ocean

合作研究：应用一种新方法将海洋中微生物的生长效率、功能和能量转移联系起来

• 批准号: 2219794
• 负责人: Kimberly Popendorf
• 金额: $ 59.72万
• 依托单位: University of Miami
• 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: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2219794&HistoricalAwards=false
• 关键词: Collaborative; Research; Applying; novel; approach

This project investigates the factors determining where and why microbes are the most efficient at turning carbon into biomass within the upper several hundred meters of the ocean. Microbial growth efficiency is a critical ecological parameter that describes the energy required by microbes for biomass production and defines the proportion of carbon lost from marine microbial food webs through respiration—conversion of organic carbon into carbon dioxide. Despite its significance, there is a limited understanding of the drivers of microbial efficiency. Assessing microbial efficiency variation across different marine microbes is hindered by the difficulty of directly measuring the energy used for biomass production. This project uses new methods to estimate microbial energy conversion within cells and compare it to measurements of other metabolic processes such as respiration and primary production. Additionally, the researchers measure environmental nutrient concentration, oxygen concentration, temperature, pH, and microbial community structure from diverse oceanographic environments in the California Current ecosystem to include within mathematical models for interpreting and predicting microbial carbon flow. In addition, this project provides education and at-sea research training opportunities for new scientists, including graduate students, postdoctoral scholars, and a cohort of undergraduate students from groups historically underrepresented in the marine sciences. This project aims to identify the ecological conditions and microbial taxa that account for the variance in microbial growth efficiency along light and nutrient gradients in the ocean. The project uses data collected on an oceanographic research expedition in the California Current ecosystem along the central and southern California coast, a well-characterized and heterogenous region broadly representative of key ecosystems in the global ocean. Microbial growth efficiency measurements are being made using an innovative combination of two new radioisotope tracer-based techniques, flow cytometry, and microbial community structure analysis. In addition, the researchers use machine learning techniques to provide predictive analytics and link microbial community structure, abundance, efficiency, and environmental conditions.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.

该项目研究了决定海洋上层数百米范围内微生物将碳转化为生物质的效率最高的因素和原因。微生物生长效率是一个关键的生态参数，它描述了微生物生产生物质所需的能量，并定义了微生物的生长效率。海洋微生物食物网通过呼吸作用（有机碳转化为二氧化碳）损失的比例尽管具有重要意义，但对不同海洋微生物效率的驱动因素的了解还很有限。由于难以直接测量用于生物质生产的能量，微生物的研究受到阻碍。该项目使用新方法来估计细胞内的微生物能量转化，并将其与其他代谢过程（例如呼吸和初级生产）的测量结果进行比较。此外，研究人员还测量环境。加州海流生态系统中不同海洋环境集中的营养物、氧气浓度、温度、pH 值和微生物群落结构，包括在解释和预测微生物碳流的数学模型中。此外，该项目还提供教育和海上研究培训机会。为了新科学家，包括研究生、博士后学者和一群来自海洋科学领域历史上代表性不足的群体的本科生，该项目旨在确定导致微生物生长效率沿光和营养梯度变化的生态条件和微生物分类群。该项目使用了在加州中部和南部海岸的加州海流生态系统中收集的数据，该区域是一个特征明确且异质的区域，广泛代表了全球海洋中的关键生态系统。利用两种基于放射性同位素示踪剂的新型技术、流式细胞术和微生物群落结构分析的创新组合，研究人员利用机器学习技术提供预测分析并将微生物群落结构、丰度、效率和环境条件联系起来。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。