Dataset Information

Taxonomic and functional analyses of intact microbial communities thriving in extreme, astrobiology-relevant, anoxic sites.

ABSTRACT:

Background

Extreme terrestrial, analogue environments are widely used models to study the limits of life and to infer habitability of extraterrestrial settings. In contrast to Earth's ecosystems, potential extraterrestrial biotopes are usually characterized by a lack of oxygen.

Methods

In the MASE project (Mars Analogues for Space Exploration), we selected representative anoxic analogue environments (permafrost, salt-mine, acidic lake and river, sulfur springs) for the comprehensive analysis of their microbial communities. We assessed the microbiome profile of intact cells by propidium monoazide-based amplicon and shotgun metagenome sequencing, supplemented with an extensive cultivation effort.

Results

The information retrieved from microbiome analyses on the intact microbial community thriving in the MASE sites, together with the isolation of 31 model microorganisms and successful binning of 15 high-quality genomes allowed us to observe principle pathways, which pinpoint specific microbial functions in the MASE sites compared to moderate environments. The microorganisms were characterized by an impressive machinery to withstand physical and chemical pressures. All levels of our analyses revealed the strong and omnipresent dependency of the microbial communities on complex organic matter. Moreover, we identified an extremotolerant cosmopolitan group of 34 poly-extremophiles thriving in all sites.

Conclusions

Our results reveal the presence of a core microbiome and microbial taxonomic similarities between saline and acidic anoxic environments. Our work further emphasizes the importance of the environmental, terrestrial parameters for the functionality of a microbial community, but also reveals a high proportion of living microorganisms in extreme environments with a high adaptation potential within habitability borders. Video abstract.

SUBMITTER: Bashir AK

PROVIDER: S-EPMC7893877 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Publications

Taxonomic and functional analyses of intact microbial communities thriving in extreme, astrobiology-relevant, anoxic sites.

Bashir Alexandra Kristin AK Wink Lisa L Duller Stefanie S Schwendner Petra P Cockell Charles C Rettberg Petra P Mahnert Alexander A Beblo-Vranesevic Kristina K Bohmeier Maria M Rabbow Elke E Gaboyer Frederic F Westall Frances F Walter Nicolas N Cabezas Patricia P Garcia-Descalzo Laura L Gomez Felipe F Malki Mustapha M Amils Ricardo R Ehrenfreund Pascale P Monaghan Euan E Vannier Pauline P Marteinsson Viggo V Erlacher Armin A Tanski George G Strauss Jens J Bashir Mina M Riedo Andreas A Moissl-Eichinger Christine C

Microbiome 20210218 1

<h4>Background</h4>Extreme terrestrial, analogue environments are widely used models to study the limits of life and to infer habitability of extraterrestrial settings. In contrast to Earth's ecosystems, potential extraterrestrial biotopes are usually characterized by a lack of oxygen.<h4>Methods</h4>In the MASE project (Mars Analogues for Space Exploration), we selected representative anoxic analogue environments (permafrost, salt-mine, acidic lake and river, sulfur springs) for the comprehensi ...[more]

PMID: 33602336

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Dataset Information

Taxonomic and functional analyses of intact microbial communities thriving in extreme, astrobiology-relevant, anoxic sites.

Background

Methods

Results

Conclusions

Publications

Taxonomic and functional analyses of intact microbial communities thriving in extreme, astrobiology-relevant, anoxic sites.

Similar Datasets

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