Collaborative Research: Microdiversity drives ecosystem function: SAR11 bacteria as models for oceanic nitrogen loss

合作研究：微多样性驱动生态系统功能：SAR11 细菌作为海洋氮流失的模型

• 批准号: 2130185
• 负责人: Frank Stewart
• 金额: $ 48.68万
• 依托单位: Montana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-12-01 至 2024-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2130185&HistoricalAwards=false
• 关键词: Collaborative; Research; Microdiversity; drives; ecosystem

This project studies how low oxygen availability influences the biodiversity and ecological role of SAR11 bacteria, one of the most abundant microbial groups in the ocean. The work involves oceanographic sampling across a range of oxygen and nutrient levels in the Eastern Tropical North Pacific Ocean. Using a combination of genomic, microbiological, and biogeochemical methods, the study identifies the mechanisms by which SAR11 strains diversify into separate niches and species and contribute biochemically to the ecosystem, likely through removing nitrogen from seawater. The project equips the next generation of researchers and educators, notably those from underrepresented minority groups, to use oceanographic, genomic, and microbiological concepts to meet contemporary scientific challenges. This goal is met through a combination of bioinformatic workshops that target undergraduate students from the University System of Puerto Rico, middle school teacher-training workshops, and middle or high school teacher internships in the investigator’s labs. This multifaceted research and educational agenda fills a gap in our understanding of marine biological diversity, identifies the contribution of SAR11 bacteria to nutrient and carbon cycles in low oxygen oceans, and provides lessons and analytical tools to study microbial processes in other ecosystems.This project has two aims. Aim 1 employs comparative metagenomic and single-cell genomic analyses to identify metabolic properties that distinguish SAR11 clades from low oxygen regions and processes of selection or gene flow operating across the clades. Aim 2 combines microbial transcriptomics, incubation experiments with isotope tracers, and culturing to delimit the oxygen and nutrient conditions that define the niche space of each SAR11 clade and to correlate SAR11 gene transcription with community biochemical outcomes, including nitrogen loss through denitrification. The results of these aims and the informatic methods used to probe microbial microdiversity are disseminated through genomics-focused undergraduate workshops, and new teacher-training educational modules, including lab-based modules focused on the importance of microorganisms under environmental change in the oceans. Data, manuscripts, and informatics workflows from this project are made publicly available. The results are critical for resolving the processes that create and sustain microbial diversity in the oceans and informing biogeochemical models that predict how diversity influences ecosystem processes.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.

该项目研究低氧气利用率如何影响 SAR11 细菌的生物多样性和生态作用，SAR11 细菌是海洋中最丰富的微生物群之一。这项工作涉及利用东部热带北太平洋的一系列氧气和营养物水平进行海洋学采样。该研究结合了基因组学、微生物学和生物地球化学方法，确定了 SAR11 菌株多样化为不同生态位和物种的机制，并可能通过从海水中去除氮来对生态系统做出生化贡献。下一代研究人员和教育工作者，特别是来自代表性不足的少数群体的研究人员和教育工作者，利用海洋学、基因组和微生物学概念来应对当代科学挑战。这一目标是通过针对波多黎各大学系统本科生的生物信息学研讨会来实现的。 Rico、中学教师培训讲习班以及在研究者实验室中的初中或高中教师实习这一多方面的研究和教育议程填补了我们对海洋生物多样性理解的空白，确定了 SAR11 细菌对营养和营养的贡献。低氧海洋中的碳循环，并为研究其他生态系统中的微生物过程提供经验教训和分析工具。该项目有两个目标，采用比较宏基因组和单细胞基因组分析来确定区分 SAR11 进化枝与低氧区域的代谢特性。目标 2 结合了微生物转录组学、同位素示踪剂的孵化实验以及界定生态位的氧气和营养条件的培养过程。这些目标的结果和用于探测微生物微观多样性的信息方法通过以基因组学为重点的本科研讨会和新的教师培训进行传播。教育模块，包括基于实验室的模块，重点关注海洋环境变化下微生物的重要性。该项目的数据、手稿和信息学工作流程均已公开。对于解决在海洋中创造和维持微生物多样性的过程以及为预测多样性如何影响生态系统过程的生物地球化学模型提供信息至关重要。该奖项是 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进行评估，被认为值得支持标准。

项目成果

Novel Alphaproteobacteria transcribe genes for nitric oxide transformation at high levels in a marine oxygen-deficient zone

• DOI: 10.1128/aem.02099-23
• 发表时间: 2024-03-06
• 期刊: APPLIED AND ENVIRONMENTAL MICROBIOLOGY
• 影响因子: 4.4
• 作者: Elbon，Claire E.;Stewart，Frank J.;Glass，Jennifer B.
• 通讯作者: Glass，Jennifer B.