20-EPN-080: Structural organization and complexity of the Antarctic cryptoendolithic communities
October 8, 2022

20-EPN-080: Structural organisation and complexity of the Antarctic cryptoendolithic communities

Visit by Gerardo Antonio, Università degli Studi della Tuscia (Italy) to TA2 Facility 3 – NHM Petrology, Mineralogy and Chemistry Facility (UK).
Dates of visit: 15-19 March 2022

Report Summary: The Antarctic cryptoendolithic communities are microbial ecosystems that dominate the biology of most ice-free areas in Continental Antarctica and described for the first time in the McMurdo Dry Valleys, the largest ice-free area of the continent. The Dry Valleys are a nearly pristine environment largely undisturbed and uncontaminated by humans and show remarkable peculiarities, representing an important analogue for the conditions of ancient Earth and Mars and a model environment for astrobiological studies.

These ice-free areas are dominated mostly by oligotrophic mineral soil and rocky outcrops and, for the harshest conditions in this area, the biology is dominated by cryptic microbial life-forms dwelling inside rocks. These cryptoendolithic communities are complex and self-supporting assemblages of phototrophic and heterotrophic microorganisms, including Bacteria, Chlorophyta and both free-living and lichen-forming fungi.

Despite the recent molecular studies to investigate the biodiversity and community composition, the interaction microbes-microbes and microbes-rock matrix, the spatial organisation, rock microstructure (e.g. porosity, pore size and connectivity) are totally unexplored.

We, herein, are proposing to build an interactions network map, on colonized and not colonized sandstone, resolving the contributions of the different microorganisms and the relationships established among them and between microbial cells and the lithic substrate.