Survival limits of yeasts and other extremophilic microorganisms with relevance for planetary protection of the icy moons

Investigating the survival limits of extremophilic microorganisms exposed to simulated space conditions can shed light on the ability of terrestrial microorganisms to survive and propagate on other planetary bodies. Although microbes can be found in all environmental niches on Earth, this study focuses mainly on psychrophilic and psychrotolerant microorganisms (prokaryotes and eukaryotes) which have been isolated from locations of interest such as icy moon analogue environments and cleanrooms, and which might be of concern for forward planetary protection. Our research aimed to reproduce conditions for microorganisms on spacecraft travelling to the outer solar system, which could contaminate the icy moon’s subsurface oceans. The microorganisms were grown under oligotrophic conditions in minimal media supplemented with only a single carbon source and exposed to extreme conditions, in terms of temperature and radiation, as they occur during space travel to the outer solar system. Our resu..., Methods included growth of microorganisms in minimal media, exposure to desiccation, polychromatic UV, UV-C and X-ray radiation., , # Data from: Survival limits of yeasts and other extremophilic microorganisms with relevance for planetary protection of the icy moons Dataset DOI: [10.5061/dryad.70rxwdc7r](10.5061/dryad.70rxwdc7r) ## Description of the data and file structure Data from: Survival of extremophilic microorganisms to icy moon simulated conditions **Description of the data and file structure** The data reported here was obtained by determining the relative survival (N/N0) of the microorganisms evaluated in our study exposed to icy moon conditions. These include the exposure to freeze and thaw cycles, to freezing at -80°C without cryoprotectants, the exposure to polychromatic UV radiation, UV-C radiation and X-ray radiation. The relative survival was calculated by dividing the number of microbial colony forming units (CFU) post exposure (N) by the CFU of the control condition (N0) un-exposed to the icy moon conditions. ### Files and variables #### File: Relative_survival_to_exposure.zip **Descripti...,探究暴露于模拟太空环境下的嗜极微生物（extremophilic microorganisms）的生存极限，有助于阐释地球微生物在其他天体上存活与增殖的能力。尽管地球上所有环境生态位中均有微生物分布，但本研究主要聚焦于从冰卫星类比环境、洁净室等目标环境中分离得到的嗜冷（psychrophilic）与耐冷（psychrotolerant）微生物（包括原核生物与真核生物），这类微生物可能引发正向行星保护方面的担忧。本研究旨在模拟前往外太阳系的航天器表面微生物所处的环境——此类环境可能会污染冰卫星的次表层海洋。研究对象微生物在仅添加单一碳源的最低限培养基（minimal media）中于寡营养（oligotrophic）条件下培养，并暴露于前往外太阳系的太空飞行过程中出现的极端温度与辐射环境。本研究结果……，实验方法包括：在最低限培养基中培养微生物，使其接受干燥、多色紫外线（UV）、UV-C射线与X射线辐射处理。 # 数据来源：与冰卫星行星保护相关的酵母菌及其他嗜极微生物的生存极限 数据集DOI：[10.5061/dryad.70rxwdc7r](10.5061/dryad.70rxwdc7r) ## 数据与文件结构说明 本报告中的数据通过测定本研究中评估的微生物在暴露于冰卫星环境后的相对存活率（N/N0）获得。此类环境包括冻融循环、无低温保护剂条件下的-80℃冷冻处理，以及多色紫外线辐射、UV-C射线辐射与X射线辐射暴露。相对存活率通过将暴露处理后的微生物菌落形成单位（CFU, Colony Forming Units）数量（N）除以未暴露于冰卫星环境的对照组菌落形成单位数量（N0）计算得到。 ### 文件与变量 #### 文件：Relative_survival_to_exposure.zip **描述：** ...