54 research outputs found
Survival strategies of endoliths in terrestrial arid environments: implications for astrobiology
Microbial life in hot and cold desert environments inhabits endolithic niches. The endolithic microorganisms include bacteria, fungi and lichens. To protect themselves from the inhospitable conditions, such as high UV radiation, dryness, and rapid temperature variations, microorganisms migrate into fractures or in pore spaces where the necessary nutrient, moisture, and light are sufficient for survival. Examples of endolithic communities are well documented from the Negev Desert, Antarctica and the Artic regions, and the Atacama Desert. The most common substrates are porous, crystalline sandstones with calcium carbonate cements and sulfate (gypsum) and other evaporite mineral crusts. The detection of sulfate on the Martian surface has sparked off considerable interest in the astrobiological potential of the evaporite deposits of continental environments, which may potentially host (or may have hosted) endolithic microorganisms
Microbial colonization of the salt deposits in the driest place of the Atacama Desert (Chile)
The Atacama Desert (Chile), one of the most arid places on Earth, shows hostile
conditions for the development of epilithic microbial communities. In this study, we report
the association of cyanobacteria (Chroococcidiopsis sp.) and bacteria belonging to
Actinobacteria and Beta-Gammaproteobacteria and Firmicutes phyla inhabiting the near
surface of salt (halite) deposits of the Salar Grande Basin, Atacama Desert (Chile). The halite
deposits were investigated by using optical, confocal and field emission scanning electron
microscopes, whereas culture-independent molecular techniques, 16S rDNA clone library,
alongside RFLP analysis and 16S rRNA gene sequencing were applied to investigate the
bacterial diversity. These microbial communities are an example of life that has adapted to
extreme environmental conditions caused by dryness, high irradiation, and metal concentrations.
Their adaptation is, therefore, important in the investigation of the environmental
conditions that might be expected for life outside of Earth
Microbial colonization of the salt deposits in the driest place of the Atacama Desert (Chile)
The Atacama Desert (Chile), one of the most arid places on Earth, shows hostile
conditions for the development of epilithic microbial communities. In this study, we report
the association of cyanobacteria (Chroococcidiopsis sp.) and bacteria belonging to
Actinobacteria and Beta-Gammaproteobacteria and Firmicutes phyla inhabiting the near
surface of salt (halite) deposits of the Salar Grande Basin, Atacama Desert (Chile). The halite
deposits were investigated by using optical, confocal and field emission scanning electron
microscopes, whereas culture-independent molecular techniques, 16S rDNA clone library,
alongside RFLP analysis and 16S rRNA gene sequencing were applied to investigate the
bacterial diversity. These microbial communities are an example of life that has adapted to
extreme environmental conditions caused by dryness, high irradiation, and metal concentrations.
Their adaptation is, therefore, important in the investigation of the environmental
conditions that might be expected for life outside of Earth
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