Unveiling microbial diversity in deep geothermal fluids, from current knowledge and analogous environments

Geothermal Energy

Review

Alessio Leins¹  Andrea Vieth-Hillebrand¹  Simona Regenspurg¹  Florian Eichinger²  Joy Ianotta²  Saskia Bindschedler³  Danaé Bregnard³  Guillaume Cailleau³  Pilar Junier³  Richard Hoffmann⁴  Joerg Uhde⁴ 

[1] GFZ German Research Centre for Geosciences, Potsdam, Germany;Hydroisotop GmbH, Schweitenkirchen, Germany;Laboratory of Microbiology, University of Neuchâtel, Neuchâtel, Switzerland;Pfalzwerke Geofuture GmbH, Insheim, Germany;

关键词: Deep geothermal fluids;    Extreme microorganisms;    Deep biosphere;    16S rRNA gene sequencing;    Molecular methods;   

DOI  :  10.1186/s40517-023-00269-z

 received in 2022-05-26, accepted in 2023-09-13,  发布年份 2023

来源: Springer

【 摘 要 】

Extreme environments on Earth host a large diversity of microbial life. Bacteria, archaea, and fungi are able to survive under one or several extreme conditions including extreme ranges of temperature, pressure, pH or salinity. Despite extensive research on extremophilic microorganisms, a relatively unexplored frontier within the study of the deep biosphere is the survey of the diversity of microorganisms inhabiting deep geothermal reservoirs used for energy production. These sites offer unique access to investigate life in the deep biosphere. The conditions in these reservoirs are often within the range of the known limits of life, which makes them a suitable habitat for various extremophilic microorganisms. Moreover, microbial-driven processes such as microbially induced scaling or corrosion can decrease the efficacy of geothermal power plant systems. The present review summarizes the current knowledge and uncertainties surrounding microbial life in deep geothermal reservoirs. As the knowledge in deep geothermal fluids is still scarce, the microbial diversity in analogous environments, such as surface geothermal springs, deep-sea hydrothermal vents or deep subsurface environments, is also summarized here. The high diversity of microorganisms inhabiting these analogous environments suggests that deep geothermal fluids may host an unsuspected microbial diversity. Moreover, the challenges associated to the study of microorganisms in geothermal fluids are reviewed. These include notably challenges linked to sampling, DNA extraction from low biomass samples, DNA amplification and sequencing of unknown communities, and biases induced by comparison of the sequences obtained to reference databases. Such biases are even stronger concerning fungi and archaea, as specific databases are less extensive than those for bacteria. A broader knowledge on microorganisms in deep geothermal fluids may not only allow to reduce the negative impact of microbial activity in geothermal power plants, but could also provide new insights into the evolution of microorganisms and their survival in extreme environments.

【 授权许可】

CC BY   
© Helmholtz Centre for Environmental Research / Helmholtz-Zentrum für Umweltforschung GmbH (UFZ), Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ, Karlsruher Institut für Technologie (KIT) 2023

【 图 表 】

12888_2023_5283_Article_IEq2.gif

12888_2023_5283_Article_IEq1.gif

Fig. 3

Fig. 2

Fig. 1