Putting B-vitamins on the map: to what extent do they shape phytoplankton dynamics and biogeography in the global ocean?

让 B 族维生素名声大噪：它们在多大程度上影响全球海洋中的浮游植物动态和生物地理学？

• 批准号: 2220546
• 负责人: Sergio Sanudo-Wilhelmy
• 金额: $ 45.16万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2220546&HistoricalAwards=false
• 关键词: Putting; vitamins; map; what; extent

B-vitamins (thiamin, B1; biotin B7; cobalamin, B12) are organic molecules necessary for all the biological transformations of the chemical elements that support life on Earth. Without the activity of those molecules, the chemistry of life on Earth—as we know it—would end. In marine systems, the availability of B-vitamins also affects food web dynamics by controlling both bacterial and phytoplankton growth and species diversity. Because many organisms that can make several B-vitamins lack the ability to synthesize others, their vitamin needs and environmental accessibility could define which, when, and where specific phytoplankton species flourish. As a result, planktonic communities in nature need to constantly share B-vitamins in a complex mosaic of interdependencies. Despite the early discovery of their relevance in the 1940s, most current marine vitamin research is still based on laboratory experiments or studies focusing on the biological responses of B-vitamin additions on algae and bacteria. Yet, vitamin distributions in the world ocean are mostly unknown, as they have only been measured in a few marine basins. Thus, the actual effect of their natural distributions in phytoplankton communities is still a mystery today. The main goal of this project is to elucidate the effects of B-vitamins availability on the spatial distributions of different phytoplankton species in surface waters of the world ocean. These data are needed to start untangling the rules by which members of the microbial plankton are interconnected through vitamin exchange and to determine how these essential interrelations may control surface ocean ecosystem functioning, such as phytoplankton and bacterial growth. Ultimately understanding these controls and their dynamics is critical to predicting future changes in the marine environment. In the future greenhouse world, the ocean is expected to be of paramount importance, providing the required protein to nurture future human populations and to reduce the levels of human-produced atmospheric CO2 through its uptake by photosynthetic organisms with different vitamin requirements. This study is to establish the first global map of B-vitamin distributions in surface waters of the world ocean collected during the Malaspina circumnavigation expedition. This global map of vitamins is being used to determine their importance on phytoplankton species biogeography, a still unresolved ecological riddle. Another objective of the study is to establish how ambient vitamin concentrations, combined with bioactive trace elements and macronutrients, promote changes in the relative abundance of different eukaryotic and prokaryotic plankton species on the surface ocean. Overall, this is the first global study on the role of B-vitamins on ecosystem functioning and species composition in subtropical and tropical open ocean environments including the ocean gyres. The investigators are carrying out targeted metagenomic analyses to identify B-vitamins synthesizers and consumers within the planktonic community at several globally distributed stations across the Atlantic, Pacific, and Indian oceans. The extensive datasets already generated by the hundreds of participants of the Malaspina expedition is fully available to interpret the vitamin results. This study allows us to expand our understanding of B-vitamin distributions on a global scale and further investigate how surface ocean’s plankton community dynamics are intertwined with ambient B-vitamin pools.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.

B 族维生素（硫胺素，B1；生物素 B7；钴胺素，B12）是支持地球生命的化学元素的所有生物转化所必需的有机分子。如果没有这些分子的活动，我们所知的地球上生命的化学反应就会结束。在海洋系统中，B 族维生素的可用性还通过控制细菌和浮游植物的生长以及物种多样性来影响食物网动态。由于许多能够产生多种 B 族维生素的生物体缺乏合成其他维生素的能力，因此它们的维生素需求和环境可及性可以决定特定浮游植物物种的繁盛、时间和地点。因此，自然界中的浮游生物群落需要在复杂的相互依存关系中不断共享 B 族维生素。 尽管早在 20 世纪 40 年代就发现了它们的相关性，但目前大多数海洋维生素研究仍然基于实验室实验或研究，重点关注添加 B 族维生素对藻类和细菌的生物反应。然而，世界海洋中的维生素分布大多未知，因为仅在少数海洋盆地进行了测量。因此，它们在浮游植物群落中自然分布的实际影响至今仍然是一个谜。该项目的主要目标是阐明 B 族维生素可用性对世界海洋表层水中不同浮游植物物种空间分布的影响。需要这些数据来开始理清浮游微生物成员通过维生素交换相互联系的规则，并确定这些基本的相互关系如何控制表面海洋生态系统的功能，例如浮游植物和细菌的生长。最终了解这些控制及其动态对于预测海洋环境的未来变化至关重要。在未来的温室世界中，海洋预计将发挥至关重要的作用，提供养育未来人类所需的蛋白质，并通过具有不同维生素需求的光合生物吸收人类产生的大气二氧化碳水平。这项研究旨在建立第一张在 Malaspina 环球航行期间收集的世界海洋表层水中 B 族维生素分布的全球地图。这张全球维生素图被用来确定它们对浮游植物物种生物地理学的重要性，这是一个尚未解决的生态之谜。该研究的另一个目标是确定环境维生素浓度与生物活性微量元素和常量营养素相结合如何促进海洋表层不同真核和原核浮游生物物种相对丰度的变化。总体而言，这是第一项关于 B 族维生素对亚热带和热带公海环境（包括海洋环流）的生态系统功能和物种组成作用的全球研究。研究人员正在开展有针对性的宏基因组分析，以确定分布在大西洋、太平洋和印度洋的多个站点的浮游生物群落中的 B 族维生素合成者和消费者。 Malaspina 探险队的数百名参与者已经生成了广泛的数据集，完全可以用来解释维生素结果。这项研究使我们能够扩大对全球范围内 B 族维生素分布的了解，并进一步研究海洋表层浮游生物群落动态如何与环境 B 族维生素池相互交织。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。