Icy exposure of microorganisms

• Main Authors: Panitz, Corinna, Beblo-Vranesevic, Kristina, Cortesao, Marta, Rabbow, Elke, Moeller, Ralf and the ICEXPOSE Research Team
• Format: Conference Object
• Language: German
• Published: 2018
• Subjects: Strahlenbiologie; Antarc*; Antarctic; Ice Sheet
• Online Access: https://elib.dlr.de/124495/; https://elib.dlr.de/124495/1/ME-SBA-2018-Panitz-Beblo-EANA2018_AbstractBook.pdf; http://www.eana-net.eu/index.php?page=Conferences/EANA2018

The most hostile place on Earth with the lowest temperature ever recorded of -89.2 °C is the Antarctic ice sheet. This cold, arid, remotely located and perennially ice covered environment has long been considered an analogue to how life might persist in the frozen landscape of the major Astrobiological targets of our solar system suchasMarsortheJupiter’sice-covered moon Europa. In the frame of the ICEXPOSE project presented here the parameters outside the Antarctic Concordia station are utilized as a testbed for performed or planned long-duration space flights and to study the survivability of selected test organisms in an extremely cold (with temperature swings) and highly variable UV environment. The most likely terrestrial organisms to endure such an excursion are extremely tolerant and/or (multi-) resistant microbesextremophiles- that have evolved mechanisms to withstand such severe conditions. The survivability of a variety of human-, space-flight and extreme-associated microorganisms from all three domains of life (plus viruses) will be investigated using a multiuser exposure facility called EXPOSE that has already been successfully flown on ISS for space exposure durations of up to 2 years. The EXPOSE Mission Ground Reference (MGR) trays are still available and will be reused to accommodate the samples for passive exposure. Microbiological response to single and combined extraterrestrial conditions including simulations of astrobiological relevant environments, like simulated Martian atmospheric conditions, will be tested. The scientific questions addressed in ICEXPOSE are: how is the survival of human-associated and Polar Regionsderived microorganisms compared to (other) environmental extremophilic microorganisms; which physiological state (i.e., cells, spores or colony/biofilms) harbors the weakest or strongest viability and/or mutagenicity detectable after exposure; what type of morphologic and molecular changes can be identified and to which extent does the exposure conditions (e.g. UV-exposed versus ...