Viability of the lichen Xanthoria elegans and its symbionts after 18 months of space exposure and simulated Mars conditions on the ISS

  title={Viability of the lichen Xanthoria elegans and its symbionts after 18 months of space exposure and simulated Mars conditions on the ISS},
  author={Annette Brandt and Jean-Pierre Paul de Vera and Silvano Onofri and Sieglinde Ott},
  journal={International Journal of Astrobiology},
  pages={411 - 425}
Abstract The lichen Xanthoria elegans has been exposed to space conditions and simulated Mars-analogue conditions in the lichen and fungi experiment (LIFE) on the International Space Station (ISS). After several simulations and short space exposure experiments such as BIOPAN, this was the first long-term exposure of eukaryotic organisms to the hostile space conditions of the low Earth orbit (LEO). The biological samples were integrated in the EXPOSE-E facility and exposed for 1.5 years outside… 

Characterisation of Growth and Ultrastructural Effects of the Xanthoria elegans Photobiont After 1.5 Years of Space Exposure on the International Space Station

The ultrastructural analysis of the algal cells provided an insight to cellular damages caused by long-term exposure and highlighted that desiccation-induced breakdown of cellular integrity is more pronounced under the more severe space vacuum than under Mars-analogue atmospheric conditions.

Resistance of the Lichen Buellia frigida to Simulated Space Conditions during the Preflight Tests for BIOMEX--Viability Assay and Morphological Stability.

It is demonstrated that Buellia frigida is capable of surviving the conditions tested in EVT and SVT and will help assess the limits and limitations of terrestrial organisms under space and Mars conditions as well as characterize the adaptive traits that confer lichen extremotolerance.

Characterization of Viability of the Lichen Buellia frigida After 1.5 Years in Space on the International Space Station.

The results performed in the BIOMEX Mars simulation experiment on the ISS indicate that the potential for survival and the resistance of the lichen B. frigida to LEO conditions are very low, and it is unlikely that Mars could be inhabited by this lichen, or even not habitable planet for the tested lichen symbionts.

Survival of Antarctic Cryptoendolithic Fungi in Simulated Martian Conditions On Board the International Space Station.

High stability of the DNA in the cells was demonstrated and data 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.

Simulated Space Radiation: Impact of Four Different Types of High-Dose Ionizing Radiation on the Lichen Xanthoria elegans.

The STARLIFE campaign complements the results of the LIFE experiments at the EXPOSE-E facility on the International Space Station by testing the model organism Xanthoria elegans on its resistance to hazardous radiation that might be accumulated during long-term space exposure.

A Desert Cyanobacterium under Simulated Mars-like Conditions in Low Earth Orbit: Implications for the Habitability of Mars.

Results have implications for the hypothesis that, during Mars's climatic history, desiccation- and radiation-tolerant life-forms could have survived in habitable niches and protected niches while transported.

Adaptation of lichens to extreme conditions

It is evident that the lichen symbiosis is more tolerant to hostile conditions than its symbionts, morphological and physiological adaptations are intimately associated, and convergent evolution has resulted in similar changes in different environments.

The Effect of High-Dose Ionizing Radiation on the Isolated Photobiont of the Astrobiological Model Lichen Circinaria gyrosa.

The results of this study reveal the limits of photobiont resistance to ionizing radiation and characterize γ radiation-induced damages, and supports parallel STARLIFE studies on the lichens Circinaria gyrosa and Xanthoria elegans.

The Effect of High-Dose Ionizing Radiation on the Astrobiological Model Lichen Circinaria gyrosa.

Simulated space ionizing radiation-Gamma rays-Extremotolerance-Lichens-Circinaria gyrosa-Photosynthetic activity and epifluorescence corroborate the findings of the parallel STARLIFE studies on the effects of ionizing Radiation on the lichen Circinaria Gyrosa, its isolated photobiont, and the Lichen Xanthoria elegans.



The potential of the lichen symbiosis to cope with extreme conditions of outer space – I. Influence of UV radiation and space vacuum on the vitality of lichen symbiosis and germination capacity

The data suggest that the symbiotic features peculiar to lichens allow them to cope with the extreme conditions of outer space or even with Martian surface conditions provided suitable niche habitats are available to serve as refuges and complementary endogenous or exogenous protection mechanisms are established.

The potential of the lichen symbiosis to cope with the extreme conditions of outer space II: germination capacity of lichen ascospores in response to simulated space conditions.

Lichens, new and promising material from experiments in astrobiology

Lichens survive in space: results from the 2005 LICHENS experiment.

Findings indicate that most lichenized fungal and algal cells can survive in space after full exposure to massive UV and cosmic radiation, conditions proven to be lethal to bacteria and other microorganisms.

UV-C tolerance of symbiotic Trebouxia sp. in the space-tested lichen species Rhizocarpon geographicum and Circinaria gyrosa: role of the hydration state and cortex/screening substances

Results indicate that the physiological state of the thallus is the most important factor impairing the tolerance of Trebouxia sp.

Life at the Limits: Capacities of Isolated and Cultured Lichen Symbionts to Resist Extreme Environmental Stresses

The hypothesis that the symbiotic state considerably enhances the ability of the respective symbionts to survive exposure to extreme conditions, including the conditions of space simulation, supports the hypothesis that lichens may be suitable for use as model organisms in exobiological studies.

Whole lichen thalli survive exposure to space conditions: results of Lithopanspermia experiment with Aspicilia fruticulosa.

The Lithopanspermia space experiment was launched in 2007 with the European Biopan facility for a 10-day spaceflight on board a Russian Foton retrievable satellite, and it was concluded that Aspicilia fruticulosa was capable of repairing all space-induced damage.

Survival of rock-colonizing organisms after 1.5 years in outer space.

Evidence is provided of the differential hardiness of cryptoendolithic communities in space, which some-but not all-of those most robust microbial communities from extremely hostile regions on Earth are also partially resistant to the even more hostile environment of outer space.

Lichens as survivors in space and on Mars

  • J. Vera
  • Environmental Science, Physics
  • 2012