Collaborative Research: RUI: Microbes need frenemies: unveiling microbial relationships with protist and viruses that support deep-sea hydrothermal vent food webs

微生物（细菌和古细菌）、病毒和真核微生物之间的相互作用是海洋食物网的关键节点。这些相互作用的范围从互利关系到微生物死亡的来源。深海热液喷口的病毒-微生物和真核生物-微生物之间的相互作用影响了当地的碳循环。本项目旨在确定这些微生物相互作用，特别是那些与原菌放牧或病毒裂解细胞死亡有关的相互作用，并探索它们在不同热液喷口栖息地的差异。通过更好地了解这些关系的组成和性质，研究人员旨在建立一个更好的深海热液喷口食物网模型，并提高我们对气候变化和其他人类活动如何影响生态系统的理解。该项目的成果包括针对社区大学生的新的微生物学、海洋学和计算机科学课程。此外，它还包括在研究过程的各个阶段与本科生一起进行研究，并提供专业发展和对等指导的机会。本项目利用宏基因组学和亚转录组学研究了深海热液喷口微生物真核生物、病毒、细菌和古细菌之间的营养相互作用，并描述了这些具有生态意义的相互作用，如互惠关系、捕食者-猎物或病毒-宿主。为了实现这些目标，研究人员正在对2020年对中开曼隆起热液喷口区进行考察期间收集的针对古细菌/细菌、病毒和真核食草动物的样本进行测序。该项目的具体目标是：1)调查微生物、病毒和原生生物的组合，并确定开曼群岛中隆起的不同喷发流体的生活方式、群落组成和新陈代谢如何变化；2)确定原生生物、病毒、细菌和古细菌之间具有生态意义的相互作用，并将这些相互作用纳入与喷口相关的食物网中碳的周转和交换模型。通过模拟营养相互作用如何影响微生物死亡率，拟议的项目极大地有助于我们了解深海中最具生产力的生态系统之一中的碳命运。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical abstractEcological interactions among microbes (bacteria and archaea), viruses, and eukaryotic microorganisms are critical junctions in marine food webs. These interactions range from mutually beneficial relationships to sources of microbial mortality. Interactions between viruses-microbes and eukaryotes-microbes at deep-sea hydrothermal vents impact local carbon cycling. This project aims to identify these microbial interactions, specifically those related to cell death by protistan grazing or viral lysis, and explore how they vary across different hydrothermal vent habitats. By providing a better understanding of the composition and nature of these relationships, the investigators aim to build a better food web model of deep-sea hydrothermal vents and improve our understanding of how climate change and other human activities impact the ecosystem. Outcomes from this project include the generation of new microbiology, oceanography, and computer science curricula targeted at community college students. In addition, it involves research with undergraduate students at all stages of the research process and provides opportunities for professional development and peer-to-peer mentoring.Technical abstractThis project examines trophic interactions among microbial eukaryotes, viruses, bacteria, and archaea at deep-sea hydrothermal vents using metagenomics and metatranscriptomics and characterizes these ecologically-significant interactions, such as mutualism, predator-prey, or virus-host. The investigators are sequencing samples collected to target archaea/bacteria, viruses, and eukaryotic grazers during a 2020 expedition to the Mid-Cayman Rise hydrothermal vent field to accomplish these goals. Specific aims of this project are to 1) Investigate the microbial, viral, and protistan assemblages and determine how lifestyle, community composition, and metabolism vary across venting fluids of the Mid-Cayman Rise; and 2) Identify ecologically-significant interactions among protists, viruses, bacteria, and archaea and incorporate these interactions into a model for turnover and exchange of carbon in the vent-associated food web. By modeling how trophic interactions influence microbial mortality, the proposed project substantially contributes to our understanding of the fate of carbon in one of the most productive ecosystems of the deep sea.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.