 |
| Titel |
BIOMEX on EXPOSE-R2: First results on the preservation of Raman biosignatures after space exposure |
| VerfasserIn |
Mickael Baqué, Ute Böttger, Thomas Leya, Jean-Pierre Paul de Vera |
| Konferenz |
EGU General Assembly 2017
|
| Medientyp |
Artikel
|
| Sprache |
en
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250140324
|
| Publikation (Nr.) |
 EGU/EGU2017-3697.pdf |
|
|
|
|
|
| Zusammenfassung |
| After a 15-month exposure on-board the EXPOSE-R2 space platform, situated on the outside
of the International Space Station, four astrobiology experiments successfully came back to
Earth in March and June 2016. Among them, the BIOMEX (BIOlogy and Mars
EXperiment) experiment aims at investigating the endurance of extremophiles and
stability of biomolecules under space and Mars-like conditions in the presence of
Martian mineral analogues (de Vera et al., 2012). The preservation and evolution of
Raman biosignatures under such conditions is of particular interest for guiding future
search-for-life missions to Mars (and other planetary objects) carrying Raman spectrometers
(such as the Raman Laser Spectrometer instrument on board the future ExoMars
rover). The photoprotective carotenoid pigments (present either in photosynthetic
organisms such as plants, algae, cyanobacteria and in some bacteria and archaea)
have been classified as high priority targets for biomolecule detection on Mars and
therefore used as biosignature models due to their stability and easy identification
by Raman spectroscopy (Böttger et al., 2012). We report here on the first results
from the analysis of two carotenoids containing organisms: the cyanobacterium
Nostoc sp. (strain CCCryo 231-06; = UTEX EE21 and CCMEE 391) isolated from
Antarctica and the green alga cf. Sphaerocystis sp. (strain CCCryo 101-99) isolated from
Spitsbergen. Desiccated cells of these organisms were exposed to space and simulated
Mars-like conditions in space in the presence of two Martian mineral analogues
(phyllosilicatic and sulfatic Mars regolith simulants) and a Lunar regolith analogue
and analyzed with a 532nm Raman microscope at 1mW laser power. Carotenoids
in both organisms were surprisingly still detectable at relatively high levels after
being exposed for 15 months in Low Earth Orbit to UV, cosmic rays, vacuum (or
Mars-like atmosphere) and temperatures stresses regardless of the mineral matrix
used. Further analyses will help us to correlate these results with survival potential,
cellular damages or stability and the different extremophiles tested in the BIOMEX
experiment.
Böttger, U., de Vera, J.-P., Fritz, J., Weber, I., Hübers, H.-W., and Schulze-Makuch, D.
(2012). Optimizing the detection of carotene in cyanobacteria in a martian regolith analogue
with a Raman spectrometer for the ExoMars mission. Planetary and Space Science 60,
356–362.
de Vera, J.-P., Boettger, U., Noetzel, R. de la T., Sánchez, F.J., Grunow, D., Schmitz, N.,
Lange, C., Hübers, H.-W., Billi, D., Baqué, M., et al. (2012). Supporting Mars
exploration: BIOMEX in Low Earth Orbit and further astrobiological studies on the Moon
using Raman and PanCam technology. Planetary and Space Science 74, 103–110. |
|
|
|
|
|
|