EAGER: Colonization at the Fringe of Habitability

这个项目的重点是微生物在地球上最新和最具敌意的湖泊之一：哥斯达黎加活火山博阿S火山的卡连特湖内的微生物定居和生存。地球上新生的、贫瘠的水生环境的创造是极其罕见的；因此，这项研究是研究微生物生命如何在新的湖泊中定居和进化的新方法。该项目增加了我们对早期地球和火星上宜居性的理解，早期地球和火星经历了同样恶劣的火山喷发环境，并反复发生绝育事件。这种位于活火山顶部的极端水生环境可以达到沸腾的温度，比电池酸更酸性，并经历频繁的喷发。这项研究利用现有的方案分析了自灭菌事件以来收集的样本的时间序列。DNA测序结果将随着时间的推移建立殖民和生态演替。实验室工作和随后的分析由一名女本科生领导。计划举办一场名为《极端微生物学》的公开讲座，以传播新的研究成果及其对地球和火星早期生命的影响。这项研究通过研究嗜酸菌在活火山上的时间序列分布，探索了恶劣环境中微生物的扩散、定居和生态演替。波罗·S火山峰顶火山口湖是在杀菌岩浆活动减弱后形成的，使新生的湖泊在2019年末形成。从那时起，湖水和湖底泥浆的无菌采样大约每两个月进行一次，建立了样本的时间序列。实验室对样本的调查包括16S rRNA NextGen测序和下游分析，以确定群落特征，通过一段时间来解决殖民和群落进化问题。元基因组学结果被用来探索在这种恶劣环境中生存的遗传适应，包括减少有毒金属影响的功能途径，例如极高浓度的砷。已确定的潜在代谢途径正在与从共同采样的湖液中得出的化学能量估计进行比较。这项研究的结果提供了基线数据，以解决殖民的时间尺度和群落特征的变化，随着时间的推移，地球上最新和最有活力的湖泊之一。这些发现对地球上早期微生物的生存具有直接影响，对地球上生命的早期进化具有重大影响。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project focuses on microbial colonization and survival within one of the newest and most hostile lakes on the planet: Laguna Caliente in the active Poás volcano in Costa Rica. The creation of nascent, sterile, aquatic environments on Earth are exceedingly rare; thus, this research is a novel approach in studying how microbial life can colonize and evolve in a new lake. The project increases our understanding of habitability on early Earth and Mars, which experienced equally harsh hydro-volcanic settings with repeated sterilization events. This extreme aquatic environment on top of an active volcano can reach boiling temperatures, is more acidic than battery acid, and experiences frequent eruptions. This research analyzes a time series of samples collected since the sterilization event utilizing existing protocols. DNA sequencing results will establish colonization and ecological succession through time. The laboratory work and subsequent analyses is led by a female undergraduate student. A public lecture on ‘microbiology at the extreme’ is planned to disseminate novel research results and the implications for early life on Earth and Mars.This research explores microbial dispersal, colonization, and ecological succession in a hostile environment by examining the time-series distribution of Acidiphilium bacteria across an active volcano. The Poás volcano summit crater lake was created after the sterilizing magmatic activity waned, allowing the nascent lake to form in late 2019. Since then, aseptic sampling of the lake fluids and lake bottom muds has occurred on a roughly two-month cadence, establishing a time-series of samples. Laboratory investigations of the samples include 16S rRNA NextGen sequencing and downstream analyses to determine community characteristics through time to address colonization and community evolution. Metagenomics results are used to probe genetic adaptations that confer survival in this harsh environment, including functional pathways to reduce the effects of toxic metals, such as the extremely high concentrations of arsenic. Identified potential metabolic pathways are being compared to chemical energy estimates derived from co-sampled lake fluids. The results of this study provide baseline data to address the timescales for colonization and the changes in community characteristics through time for one of the newest and most dynamic lakes on Earth. These findings have direct implications for early microbial survival on Earth with significant implications for the early evolution of life on our planet.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.