Milojevic Tetyana, Cramm Margaret Anne, Hubert Casey R J, Westall Frances
Exobiology Group, CNRS-Centre de Biophysique Moléculaire, University of Orléans, Rue Charles Sadron, CEDEX 2, 45071 Orléans, France.
Geomicrobiology Group, Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada.
Microorganisms. 2022 Dec 6;10(12):2417. doi: 10.3390/microorganisms10122417.
New detections of thermophiles in psychrobiotic (i.e., bearing cold-tolerant life forms) marine and terrestrial habitats including Arctic marine sediments, Antarctic accretion ice, permafrost, and elsewhere are continually being reported. These microorganisms present great opportunities for microbial ecologists to examine biogeographical processes for spore-formers and non-spore-formers alike, including dispersal histories connecting warm and cold biospheres. In this review, we examine different examples of thermophiles in cryobiotic locations, and highlight exploration of thermophiles at cold temperatures under laboratory conditions. The survival of thermophiles in psychrobiotic environments provokes novel considerations of physiological and molecular mechanisms underlying natural cryopreservation of microorganisms. Cultures of thermophiles maintained at low temperature may serve as a non-sporulating laboratory model for further exploration of metabolic potential of thermophiles at psychrobiotic temperatures, as well as for elucidating molecular mechanisms behind natural preservation and adaptation to psychrobiotic environments. These investigations are highly relevant for the search for life on other cold and icy planets in the Solar System, such as Mars, Europa and Enceladus.
不断有报道称，在嗜冷生物（即存在耐寒生命形式）的海洋和陆地栖息地，包括北极海洋沉积物、南极堆积冰、永久冻土及其他地方，发现了嗜热微生物。这些微生物为微生物生态学家提供了绝佳机会，用以研究产孢菌和非产孢菌的生物地理过程，包括连接温暖和寒冷生物圈的扩散历史。在本综述中，我们研究了低温生物环境中嗜热微生物的不同实例，并着重介绍了在实验室条件下对低温嗜热微生物的探索。嗜热微生物在嗜冷生物环境中的存活引发了对微生物自然冷冻保存背后生理和分子机制的全新思考。低温保存的嗜热微生物培养物可作为一种非产孢实验室模型，用于进一步探索嗜热微生物在嗜冷生物温度下的代谢潜力，以及阐明自然保存和适应嗜冷生物环境背后的分子机制。这些研究对于在太阳系中其他寒冷冰封行星（如火星、木卫二和土卫二）上寻找生命具有高度相关性。
