EXTREME BACFINDER: MICROBIAL DIVERSITY AND DISTRIBUTION WITHIN THE VICINITY OF THE CONCORDIA ANTARCTIC STATION.

The extreme terrestrial environment of the Antarctic ice sheet serves as an excellent probing ground for the adaptation of extremotolerant microorganisms. To inhabit this hostile environment, microorganisms resist sub-zero temperatures, wide temperature fluctuations, high incidence of solar UV radiation, desiccation, and very low nutrient availability. The propagation of microorganisms, and in particular, human-associated and potential pathogenic species, can be facilitated through numerous exposure routes (e.g. air, personal contact, water, excretions, etc.). The Concordia Research Station is a confined, isolated habitat, providing an ideal location to monitor the indigenous microbial diversity and the dispersal of humanassociated microorganisms on the surface of continental Antarctica. The BacFinder project (ESA project No. AO-13-Concordia-23) encompassed a two-year study (2015-2016), during which surface snow was sampled monthly at three areas varying in proximity (10 m, 500 m, and 1 km) to the Concordia Station. As a preliminary investigation, the snow samples from months January, March, May, July, September, and November of both years (n=36) were phylogenetically profiled via sequencing of the 16S rRNA gene to identify microbial presence and abundance with respect to spatial and temporal vectors. This study highlighted a robust examination of in-situ microbial community structure of the Antarctic habitat and enabled a deeper understanding of the extent to which human contamination has potentially spread from the Concordia Research Station. Ultimately, this study will further inform improvements or modifications to the existing methods and techniques to interrogate the microbial ecology in extreme (sub-zero) environments as well as provide suggestions for future life-detection driven space missions. [ABSTRACT FROM AUTHOR]