title: Survival of Antarctic Cryptoendolithic Fungi in Simulated Martian Conditions On Board the International Space Station.
abstract: Dehydrated Antarctic cryptoendolithic communities and colonies of the rock inhabitant black fungi Cryomyces antarcticus (CCFEE 515) and Cryomyces minteri (CCFEE 5187) were exposed as part of the Lichens and Fungi Experiment (LIFE) for 18 months in the European Space Agency's EXPOSE-E facility to simulated martian conditions aboard the International Space Station (ISS). Upon sample retrieval, survival was proved by testing colony-forming ability, and viability of cells (as integrity of cell membrane) was determined by the propidium monoazide (PMA) assay coupled with quantitative PCR tests. Although less than 10% of the samples exposed to simulated martian conditions were able to proliferate and form colonies, the PMA assay indicated that more than 60% of the cells and rock communities had remained intact after the "Mars exposure." Furthermore, a high stability of the DNA in the cells was demonstrated. The results contribute to assessing the stability of resistant microorganisms and biosignatures on the surface of Mars, data that are valuable information for further search-for-life experiments on Mars.
  
  
  BACKGROUND
  Endoliths-Eukaryotes-Extremophilic microorganisms-Mars-Radiation resistance.
authors.affiliation: 1 Department of Ecological and Biological Sciences, University of Tuscia , Viterbo, Italy .
authors.forename: Silvano
authors.initials: S
authors.lastname: Onofri
authors.affiliation: 2 Institute of Planetary Research, German Aerospace Center (DLR) , Berlin, Germany .
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: de Vera
authors.affiliation: 1 Department of Ecological and Biological Sciences, University of Tuscia , Viterbo, Italy .
authors.forename: Laura
authors.initials: L
authors.lastname: Zucconi
authors.affiliation: 1 Department of Ecological and Biological Sciences, University of Tuscia , Viterbo, Italy .
authors.forename: Laura
authors.initials: L
authors.lastname: Selbmann
authors.affiliation: 1 Department of Ecological and Biological Sciences, University of Tuscia , Viterbo, Italy .
authors.forename: Giuliano
authors.initials: G
authors.lastname: Scalzi
authors.affiliation: 3 Jet Propulsion Laboratory, California Institute of Technology , Pasadena, California, USA .
authors.forename: Kasthuri J
authors.initials: KJ
authors.lastname: Venkateswaran
authors.affiliation: 4 Institute of Aerospace Medicine, German Aerospace Center (DLR) , Cologne, Germany .
authors.forename: Elke
authors.initials: E
authors.lastname: Rabbow
authors.affiliation: 5 Department of Earth Observation, Spanish Aerospace Research Establishment-INTA , Torrejón de Ardoz, Madrid, Spain .
authors.forename: Rosa
authors.initials: R
authors.lastname: de la Torre
authors.affiliation: 4 Institute of Aerospace Medicine, German Aerospace Center (DLR) , Cologne, Germany .
authors.forename: Gerda
authors.initials: G
authors.lastname: Horneck
mesh_terms: D000864:Antarctic Regions; D001203:Ascomycota / Q000235:genetics; D001272:Atmosphere; D015169:Colony Count, Microbial; D004271:DNA, Fungal / Q000032:analysis*; D005118:Extraterrestrial Environment; D018535:Mars; D050296:Microbial Viability; D013026:Space Flight; D018561:Space Simulation; D018531:Spacecraft
chemical_list: D004271:DNA, Fungal