Jehlička Jan, Oren Aharon, Vítek Petr, Wierzchos Jacek
Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University, Prague, Czechia.
Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus, Jerusalem, Israel.
Front Microbiol. 2024 Aug 20;15:1397437. doi: 10.3389/fmicb.2024.1397437. eCollection 2024.
Microorganisms inhabiting gypsum have been observed in environments that differ greatly in water availability. Gypsum colonized by microorganisms, including cyanobacteria, eukaryotic algae, and diverse heterotrophic communities, occurs in hot, arid or even hyperarid environments, in cold environments of the Antarctic and Arctic zones, and in saline and hypersaline lakes and ponds where gypsum precipitates. Fossilized microbial remnants preserved in gypsum were also reported. Gypsum protects the endolithic microbial communities against excessive insolation and ultraviolet radiation, while allowing photosynthetically active radiation to penetrate through the mineral substrate. We here review the worldwide occurrences of microbially colonized gypsum and the specific properties of gypsum related to its function as a substrate and habitat for microbial life on Earth and possibly beyond. Methods for detecting and characterizing endolithic communities and their biomarkers in gypsum are discussed, including microscopic, spectroscopic, chemical, and molecular biological techniques. The modes of adaptation of different microorganisms to life within gypsum crystals under different environmental conditions are described. Finally, we discuss gypsum deposits as possible targets for the search for microbial life or its remnants beyond Earth, especially on Mars, where sulfate-rich deposits occur, and propose strategies to detect them during space exploration missions.
在水分可利用性差异极大的环境中，人们观察到了栖息于石膏中的微生物。被微生物（包括蓝细菌、真核藻类和各种异养群落）定殖的石膏，出现在炎热、干旱甚至极度干旱的环境中，出现在南极和北极地区的寒冷环境中，以及石膏沉淀的盐碱湖和超盐湖及池塘中。也有报道称在石膏中保存有微生物化石遗迹。石膏保护内生微生物群落免受过度日晒和紫外线辐射，同时允许光合有效辐射穿透矿物基质。我们在此综述了全球范围内微生物定殖石膏的情况，以及石膏与它作为地球上乃至可能地球以外微生物生命的基质和栖息地的功能相关的特殊性质。讨论了检测和表征石膏中内生群落及其生物标志物的方法，包括显微镜、光谱、化学和分子生物学技术。描述了不同微生物在不同环境条件下适应石膏晶体内部生活的方式。最后，我们讨论了石膏矿床作为在地球以外寻找微生物生命或其遗迹的可能目标，特别是在火星上，那里存在富含硫酸盐的矿床，并提出了在太空探索任务中检测它们的策略。
