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Lorenz C, Bianchi E, Alberini A, Poggiali G, Benesperi R, Papini A, Brucato JR. UV photo-degradation of the secondary lichen substance parietin: A multi-spectroscopic analysis in astrobiology perspective. Life Sci Space Res (Amst) 2024; 41:191-201. [PMID: 38670647 DOI: 10.1016/j.lssr.2024.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/20/2024] [Accepted: 03/21/2024] [Indexed: 04/28/2024]
Abstract
The cortical anthraquinone yellow-orange pigment parietin is a secondary lichen substance providing UV-shielding properties that is produced by several lichen species. In our work, the secondary metabolite has been extracted from air-dried thalli of Xanthoria parietina. The aims of this study were to characterize parietin absorbance through UV-VIS spectrophotometry and with IR spectroscopy and to evaluate its photodegradability under UV radiation through in situ reflectance IR spectroscopy to understand to what extent the substance may have a photoprotective role. This allows us to relate parietin photo-degradability to the lichen UV tolerance in its natural terrestrial habitat and in extreme environments relevant for astrobiology such as Mars. Extracted crystals were UV irradiated for 5.59 h under N2 flux. After the UV irradiation, we assessed relevant degradations in the 1614, 1227, 1202, 1160 and 755 cm-1 bands. However, in light of Xanthoria parietina survivability in extreme conditions such as space- and Mars-simulated ones, we highlight parietin UV photo-resistance and its relevance for astrobiology as photo-protective substance and possible bio-hint.
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Affiliation(s)
- Christian Lorenz
- Department of Biology, University of Naples Federico II, Via Cinthia, 80126 Naples, Italy; INAF-Astrophysical Observatory of Arcetri, Largo E. Fermi 5, 50125 Florence, Italy; Department of Biology, University of Florence, Via La Pira 4, 50121 Florence, Italy
| | - Elisabetta Bianchi
- Department of Biology, University of Florence, Via La Pira 4, 50121 Florence, Italy
| | - Andrew Alberini
- INAF-Astrophysical Observatory of Arcetri, Largo E. Fermi 5, 50125 Florence, Italy
| | - Giovanni Poggiali
- INAF-Astrophysical Observatory of Arcetri, Largo E. Fermi 5, 50125 Florence, Italy; LESIA-Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 place Jules Janssen, 92190 Meudon, France
| | - Renato Benesperi
- Department of Biology, University of Florence, Via La Pira 4, 50121 Florence, Italy
| | - Alessio Papini
- Department of Biology, University of Florence, Via La Pira 4, 50121 Florence, Italy
| | - John Robert Brucato
- INAF-Astrophysical Observatory of Arcetri, Largo E. Fermi 5, 50125 Florence, Italy.
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2
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Lorenz C, Bianchi E, Poggiali G, Alemanno G, Benesperi R, Brucato JR, Garland S, Helbert J, Loppi S, Lorek A, Maturilli A, Papini A, de Vera JP, Baqué M. Survivability of the lichen Xanthoria parietina in simulated Martian environmental conditions. Sci Rep 2023; 13:4893. [PMID: 36966209 PMCID: PMC10039903 DOI: 10.1038/s41598-023-32008-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 03/21/2023] [Indexed: 03/27/2023] Open
Abstract
Xanthoria parietina (L.) Th. Fr. is a widely spread foliose lichen showing high tolerance against UV-radiation thanks to parietin, a secondary lichen substance. We exposed samples of X. parietina under simulated Martian conditions for 30 days to explore its survivability. The lichen's vitality was monitored via chlorophyll a fluorescence that gives an indication for active light reaction of photosynthesis, performing in situ and after-treatment analyses. Raman spectroscopy and TEM were used to evaluate carotenoid preservation and possible variations in the photobiont's ultrastructure respectively. Significant differences in the photo-efficiency between UV irradiated samples and dark-kept samples were observed. Fluorescence values correlated with temperature and humidity day-night cycles. The photo-efficiency recovery showed that UV irradiation caused significant effects on the photosynthetic light reaction. Raman spectroscopy showed that the carotenoid signal from UV exposed samples decreased significantly after the exposure. TEM observations confirmed that UV exposed samples were the most affected by the treatment, showing chloroplastidial disorganization in photobionts' cells. Overall, X. parietina was able to survive the simulated Mars conditions, and for this reason it may be considered as a candidate for space long-term space exposure and evaluations of the parietin photodegradability.
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Affiliation(s)
- Christian Lorenz
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - Elisabetta Bianchi
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - Giovanni Poggiali
- LESIA-Observatoire de Paris, CNRS, Université PSL, Sorbonne Université, Université de Paris, 5 Place Jules Janssen, 92190, Meudon, France
- INAF-Astrophysical Observatory of Arcetri, Largo E. Fermi 5, 50125, Florence, Italy
| | - Giulia Alemanno
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Renato Benesperi
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - John Robert Brucato
- INAF-Astrophysical Observatory of Arcetri, Largo E. Fermi 5, 50125, Florence, Italy.
| | - Stephen Garland
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Jörn Helbert
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Stefano Loppi
- Department of Environmental Sciences, University of Siena, Via P. A. Mattioli 4, 53100, Siena, Italy
| | - Andreas Lorek
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Alessandro Maturilli
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Alessio Papini
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - Jean-Pierre de Vera
- Microgravity User Support Center (MUSC), Space Operations and Astronaut Training, German Aerospace Center (DLR), Linder Höhe, 51147, Cologne, Germany
| | - Mickaël Baqué
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
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Osterhout JT, Schopf JW, Kudryavtsev AB, Czaja AD, Williford KH. Deep-UV Raman Spectroscopy of Carbonaceous Precambrian Microfossils: Insights into the Search for Past Life on Mars. Astrobiology 2022; 22:1239-1254. [PMID: 36194869 DOI: 10.1089/ast.2021.0135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The current strategy for detecting evidence of ancient life on Mars-a primary goal of NASA's ongoing Mars 2020 mission-is based largely on knowledge of Precambrian life and of its preservation in Earth's early rock record. The fossil record of primitive microorganisms consists mainly of stromatolites and other microbially influenced sedimentary structures, which occasionally preserve microfossils or other geochemical traces of life. Raman spectroscopy is an invaluable tool for identifying such signs of life and is routinely performed on Precambrian microfossils to help establish their organic composition, degree of thermal maturity, and biogenicity. The Mars 2020 rover, Perseverance, is equipped with a deep-ultraviolet (UV) Raman spectrometer as part of the SHERLOC (Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals) instrument, which will be used in part to characterize the preservation of organic matter in the ancient sedimentary rocks of Jezero crater and therein search for possible biosignatures. To determine the deep-UV Raman spectra characteristic of ancient microbial fossils, this study analyzes individual microfossils from 14 Precambrian cherts using deep-UV (244 nm) Raman spectroscopy. Spectra obtained were measured and calibrated relative to a graphitic standard and categorized according to the morphology and depositional environment of the fossil analyzed and its Raman-indicated thermal maturity. All acquired spectra of the fossil kerogens include a considerably Raman-enhanced and prominent first-order Raman G-band (∼1600 cm-1), whereas its commonly associated D-band (∼1350 cm-1) is restricted to specimens of lower thermal maturity (below greenschist facies) that thus have the less altered biosignature indicative of relatively well-preserved organic matter. If comparably preserved, similar characteristics would be expected to be exhibited by microfossils or ancient organic matter in rock samples collected and cached on Mars in preparation for future sample return to Earth.
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Affiliation(s)
- Jeffrey T Osterhout
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, California, USA
- Center for the Study of Evolution and the Origin of Life, University of California, Los Angeles, California, USA
| | - J William Schopf
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, California, USA
- Center for the Study of Evolution and the Origin of Life, University of California, Los Angeles, California, USA
| | - Anatoliy B Kudryavtsev
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, California, USA
- Center for the Study of Evolution and the Origin of Life, University of California, Los Angeles, California, USA
| | - Andrew D Czaja
- Department of Geology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Kenneth H Williford
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
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Canizarès A, Foucher F, Baqué M, de Vera JP, Sauvage T, Wendling O, Bellamy A, Sigot P, Georgelin T, Simon P, Westall F. In Situ Raman Spectroscopy Monitoring of Material Changes During Proton Irradiation. Appl Spectrosc 2022; 76:723-729. [PMID: 35128962 DOI: 10.1177/00037028211062943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Organic molecules are prime targets in the search for life on other planetary bodies in the Solar System. Understanding their preservation potential and detectability after ionic irradiation, with fluences potentially representing those received for several millions to billions of years at Mars or in interplanetary space, is a crucial goal for astrobiology research. In order to be able to perform in situ characterization of such organic molecules under ionic irradiation in the near future, a feasibility experiment was performed with polymer test samples to validate the optical configuration and the irradiation chamber geometry. We present here a Raman in situ investigation of the evolution of a series of polymers during proton irradiation. To achieve this goal, a new type of Raman optical probe was designed, which documented that proton irradiation (with a final fluence of 3.1014 at·cm-2) leads to an increase in the background level of the signal, potentially explained by the scission of the polymeric chains and by atom displacements creating defects in the materials. To improve the setup further, a micro-Raman probe and a temperature-controlled sample holder are under development to provide higher spectral and spatial resolutions (by reducing the depth of field and laser spot size), to permit Raman mapping as well as to avoid any thermal effects.
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Affiliation(s)
- Aurelien Canizarès
- Center National de la Recherche Scientifique (CNRS), Conditions Extrêmes et Matériaux: Haute Température et Irradiation (CEMHTI), UPR3079, 27051University of Orléans, Orléans, France
| | - Frederic Foucher
- Centre de Biophysique Moléculaire (CBM), 27051Center National de la Recherche Scientifique, UPR 4301 Orléans Cedex 2, France
| | - Mickael Baqué
- Department of Planetary Laboratories, Astrobiological Laboratories, Institute of Planetary Research, 14930German Aerospace Center (DLR), Berlin, Germany
| | - Jean-Pierre de Vera
- Space Operations and Astronaut Training, MUSC, 14930German Aerospace Center (DLR), Cologne, Germany
| | - Thierry Sauvage
- Center National de la Recherche Scientifique (CNRS), Conditions Extrêmes et Matériaux: Haute Température et Irradiation (CEMHTI), UPR3079, 27051University of Orléans, Orléans, France
| | - Olivier Wendling
- Center National de la Recherche Scientifique (CNRS), Conditions Extrêmes et Matériaux: Haute Température et Irradiation (CEMHTI), UPR3079, 27051University of Orléans, Orléans, France
| | - Aurelien Bellamy
- Center National de la Recherche Scientifique (CNRS), Conditions Extrêmes et Matériaux: Haute Température et Irradiation (CEMHTI), UPR3079, 27051University of Orléans, Orléans, France
| | - Paul Sigot
- Center National de la Recherche Scientifique (CNRS), Conditions Extrêmes et Matériaux: Haute Température et Irradiation (CEMHTI), UPR3079, 27051University of Orléans, Orléans, France
| | - Thomas Georgelin
- Centre de Biophysique Moléculaire (CBM), 27051Center National de la Recherche Scientifique, UPR 4301 Orléans Cedex 2, France
| | - Patrick Simon
- Center National de la Recherche Scientifique (CNRS), Conditions Extrêmes et Matériaux: Haute Température et Irradiation (CEMHTI), UPR3079, 27051University of Orléans, Orléans, France
| | - Frances Westall
- Centre de Biophysique Moléculaire (CBM), 27051Center National de la Recherche Scientifique, UPR 4301 Orléans Cedex 2, France
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Cassaro A, Pacelli C, Baqué M, de Vera JPP, Böttger U, Botta L, Saladino R, Rabbow E, Onofri S. Fungal Biomarkers Stability in Mars Regolith Analogues after Simulated Space and Mars-like Conditions. J Fungi (Basel) 2021; 7:jof7100859. [PMID: 34682280 PMCID: PMC8540304 DOI: 10.3390/jof7100859] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/08/2021] [Accepted: 10/09/2021] [Indexed: 11/18/2022] Open
Abstract
The discovery of life on other planets and moons in our solar system is one of the most important challenges of this era. The second ExoMars mission will look for traces of extant or extinct life on Mars. The instruments on board the rover will be able to reach samples with eventual biomarkers until 2 m of depth under the planet’s surface. This exploration capacity offers the best chance to detect biomarkers which would be mainly preserved compared to samples on the surface which are directly exposed to harmful environmental conditions. Starting with the studies of the endolithic meristematic black fungus Cryomyces antarcticus, which has proved its high resistance under extreme conditions, we analyzed the stability and the resistance of fungal biomarkers after exposure to simulated space and Mars-like conditions, with Raman and Gas Chromatography–Mass Spectrometry, two of the scientific payload instruments on board the rover.
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Affiliation(s)
- Alessia Cassaro
- Department of Ecological and Biological Sciences, University of Tuscia, Largo Dell’Università snc, 01100 Viterbo, Italy; (A.C.); (L.B.); (R.S.); (S.O.)
| | - Claudia Pacelli
- Department of Ecological and Biological Sciences, University of Tuscia, Largo Dell’Università snc, 01100 Viterbo, Italy; (A.C.); (L.B.); (R.S.); (S.O.)
- Italian Space Agency, Via del Politecnico snc, 00133 Rome, Italy
- Correspondence: ; Tel.: +39-068567466
| | - Mickael Baqué
- German Aerospace Center (DLR), Planetary Laboratories Department, Institute of Planetary Research, Ruthefordstraße 2, 12489 Berlin, Germany;
| | - Jean-Pierre Paul de Vera
- MUSC, German Aerospace Center (DLR), Space Operations and Astronaut Training, 51147 Köln, Germany;
| | - Ute Böttger
- German Aerospace Center (DLR), Institute of Optical Sensor Systems, 12489 Berlin, Germany;
| | - Lorenzo Botta
- Department of Ecological and Biological Sciences, University of Tuscia, Largo Dell’Università snc, 01100 Viterbo, Italy; (A.C.); (L.B.); (R.S.); (S.O.)
| | - Raffaele Saladino
- Department of Ecological and Biological Sciences, University of Tuscia, Largo Dell’Università snc, 01100 Viterbo, Italy; (A.C.); (L.B.); (R.S.); (S.O.)
| | - Elke Rabbow
- Radiation Biology Division, Institute of Aerospace Medicine, DLR, Linder Höhe, 51147 Köln, Germany;
| | - Silvano Onofri
- Department of Ecological and Biological Sciences, University of Tuscia, Largo Dell’Università snc, 01100 Viterbo, Italy; (A.C.); (L.B.); (R.S.); (S.O.)
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Rouquette L, Stalport F, Cottin H, Colas C, Georgelin T, Chaouche-Mechidal N, Lasne J, Mahfouf S, Raulin F, Selliez L, Szopa C, Coll P. Dimerization of Uracil in a Simulated Mars-like UV Radiation Environment. Astrobiology 2020; 20:1363-1376. [PMID: 33179968 DOI: 10.1089/ast.2019.2157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The search for organic molecules at the surface of Mars is a key objective in astrobiology, given that many organic compounds are possible biosignatures and their presence is of interest with regard to the habitability of Mars. Current environmental conditions at the martian surface are harsh and affect the stability of organic molecules. For this reason, and because current and future Mars rovers collect samples from the upper surface layer, it is important to assess the fate of organic molecules under the conditions at the martian surface. Here, we present an experimental study of the evolution of uracil when exposed to UV radiation, pressure, and temperature conditions representative of the surface of Mars. Uracil was selected because it is a nucleobase that composes RNA, and it has been detected in interplanetary bodies that could be the exogenous source of this molecule by meteoritic delivery to the surface of Mars. Our results show that the experimental quantum efficiency of photodecomposition of uracil is 0.16 ± 0.14 molecule/photon. Although these results suggest that uracil is quickly photodegraded when directly exposed to UV light on Mars, such exposure produces dimers that are more stable over time than the monomer. The identified dimers could be targets of interest for current and future Mars space missions.
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Affiliation(s)
- Laura Rouquette
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil et Université de Paris, Institut Pierre Simon Laplace, Creteil Cedex, France
| | - Fabien Stalport
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil et Université de Paris, Institut Pierre Simon Laplace, Creteil Cedex, France
| | - Hervé Cottin
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil et Université de Paris, Institut Pierre Simon Laplace, Creteil Cedex, France
| | - Cyril Colas
- Institut de Chimie Organique et Analytique (ICOA), Université d'Orléans, UMR CNRS 7311, Orléans, France
- Centre de Biophysique Moléculaire (CBM), UPR CNRS 4301, Université d'Orléans, Orléans, France
| | - Thomas Georgelin
- Centre de Biophysique Moléculaire (CBM), UPR CNRS 4301, Université d'Orléans, Orléans, France
- Laboratoire de Réactivité de Surface, UMR CNRS 7197, Sorbonne Université, Paris, France
| | - Naïla Chaouche-Mechidal
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil et Université de Paris, Institut Pierre Simon Laplace, Creteil Cedex, France
| | - Jerome Lasne
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil et Université de Paris, Institut Pierre Simon Laplace, Creteil Cedex, France
| | - Sara Mahfouf
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil et Université de Paris, Institut Pierre Simon Laplace, Creteil Cedex, France
| | - François Raulin
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil et Université de Paris, Institut Pierre Simon Laplace, Creteil Cedex, France
| | - Laura Selliez
- Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), UMR CNRS7328, Université d'Orléans, Orléans Cedex, France
- Laboratoire atmosphères, milieux, observations spatiales, Institut Pierre Simon Laplace, UMR 8190, UVSQ Université Paris-Saclay, Sorbonne Université, CNRS, Guyancourt, France
| | - Cyril Szopa
- Laboratoire atmosphères, milieux, observations spatiales, Institut Pierre Simon Laplace, UMR 8190, UVSQ Université Paris-Saclay, Sorbonne Université, CNRS, Guyancourt, France
- Institut Universitaire de France, Paris, France
| | - Patrice Coll
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil et Université de Paris, Institut Pierre Simon Laplace, Creteil Cedex, France
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Abstract
The emerging field of astropedology is the study of ancient soils on Earth and other planetary bodies. Examination of the complex factors that control the preservation of organic matter and other biosignatures in ancient soils is a high priority for current and future missions to Mars. Though previously defined by biological activity, an updated definition of soil as planetary surfaces altered in place by biological, chemical or physical processes was adopted in 2017 by the Soil Science Society of America in response to mounting evidence of pedogenic-like features on Mars. Ancient (4.1-3.7 billion year old [Byr]) phyllosilicate-rich surface environments on Mars show evidence of sustained subaerial weathering of sediments with liquid water at circumneutral pH, which is a soil-forming process. The accumulation of buried, fossilized soils, or paleosols, has been widely observed on Earth, and recent investigations suggest paleosol-like features may be widespread across the surface of Mars. However, the complex array of preservation and degradation factors controlling the fate of biosignatures in paleosols remains unexplored. This paper identifies the dominant factors contributing to the preservation and degradation of organic carbon in paleosols through the geological record on Earth, and offers suggestions for prioritizing locations for in situ biosignature detection and Mars Sample Return across a diverse array of potential paleosols and paleoenvironments of early Mars. A compilation of previously published data and original research spanning a diverse suite of paleosols from the Pleistocene (1 Myr) to the Archean (3.7 Byr) show that redox state is the predominant control for the organic matter content of paleosols. Most notably, the chemically reduced surface horizons (layers) of Archean (2.3 Byr) paleosols have organic matter concentrations ranging from 0.014-0.25%. However, clay mineralogy, amorphous phase abundance, diagenetic alteration and sulfur content are all significant factors that influence the preservation of organic carbon. The surface layers of paleosols that formed under chemically reducing conditions with high amounts of iron/magnesium smectites and amorphous colloids should be considered high priority locations for biosignature investigation within subaerial paleoenvironments on Mars.
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Affiliation(s)
- Adrian P Broz
- Department of Earth Sciences, University of Oregon, Eugene, OR 97405, USA
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8
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Baqué M, Napoli A, Claudia F, Moeller R, de Vera JP, Billi D. Carotenoid Raman Signatures Are Better Preserved in Dried Cells of the Desert Cyanobacterium Chroococcidiopsis than in Hydrated Counterparts after High-Dose Gamma Irradiation. Life (Basel) 2020; 10:E83. [PMID: 32521820 PMCID: PMC7345886 DOI: 10.3390/life10060083] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 06/04/2020] [Accepted: 06/06/2020] [Indexed: 11/18/2022] Open
Abstract
Carotenoids are promising targets in our quest to search for life on Mars due to their biogenic origin and easy detection by Raman spectroscopy, especially with a 532 nm excitation thanks to resonance effects. Ionizing radiations reaching the surface and subsurface of Mars are however detrimental for the long-term preservation of biomolecules. We show here that desiccation can protect carotenoid Raman signatures in the desert cyanobacterium Chroococcidiopsis sp. CCMEE 029 even after high-dose gamma irradiation. Indeed, while the height of the carotenoids Raman peaks was considerably reduced in hydrated cells exposed to gamma irradiation, it remained stable in dried cells irradiated with the highest tested dose of 113 kGy of gamma rays, losing only 15-20% of its non-irradiated intensity. Interestingly, even though the carotenoid Raman signal of hydrated cells lost 90% of its non-irradiated intensity, it was still detectable after exposure to 113 kGy of gamma rays. These results add insights into the preservation potential and detectability limit of carotenoid-like molecules on Mars over a prolonged period of time and are crucial in supporting future missions carrying Raman spectrometers to Mars' surface.
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Affiliation(s)
- Mickael Baqué
- German Aerospace Center (DLR), Institute of Planetary Research, Department of Planetary Laboratories, Astrobiological Laboratories, 12489 Berlin, Germany; (M.B.); (J.-P.d.V.)
| | - Alessandro Napoli
- Department of Biology, Laboratory of Astrobiology and Molecular Biology of Cyanobacteria, University of Rome Tor Vergata, 00133 Rome, Italy; (A.N.); (C.F.)
| | - Fagliarone Claudia
- Department of Biology, Laboratory of Astrobiology and Molecular Biology of Cyanobacteria, University of Rome Tor Vergata, 00133 Rome, Italy; (A.N.); (C.F.)
| | - Ralf Moeller
- Space Microbiology Research Group, Radiation Biology Department, Institute of Aerospace Medicine, German Aerospace Center (DLR), 51147 Cologne, Germany;
| | - Jean-Pierre de Vera
- German Aerospace Center (DLR), Institute of Planetary Research, Department of Planetary Laboratories, Astrobiological Laboratories, 12489 Berlin, Germany; (M.B.); (J.-P.d.V.)
| | - Daniela Billi
- Department of Biology, Laboratory of Astrobiology and Molecular Biology of Cyanobacteria, University of Rome Tor Vergata, 00133 Rome, Italy; (A.N.); (C.F.)
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9
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Chan MA, Hinman NW, Potter-McIntyre SL, Schubert KE, Gillams RJ, Awramik SM, Boston PJ, Bower DM, Des Marais DJ, Farmer JD, Jia TZ, King PL, Hazen RM, Léveillé RJ, Papineau D, Rempfert KR, Sánchez-Román M, Spear JR, Southam G, Stern JC, Cleaves HJ. Deciphering Biosignatures in Planetary Contexts. Astrobiology 2019; 19:1075-1102. [PMID: 31335163 PMCID: PMC6708275 DOI: 10.1089/ast.2018.1903] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 03/10/2019] [Indexed: 05/05/2023]
Abstract
Microbial life permeates Earth's critical zone and has likely inhabited nearly all our planet's surface and near subsurface since before the beginning of the sedimentary rock record. Given the vast time that Earth has been teeming with life, do astrobiologists truly understand what geological features untouched by biological processes would look like? In the search for extraterrestrial life in the Universe, it is critical to determine what constitutes a biosignature across multiple scales, and how this compares with "abiosignatures" formed by nonliving processes. Developing standards for abiotic and biotic characteristics would provide quantitative metrics for comparison across different data types and observational time frames. The evidence for life detection falls into three categories of biosignatures: (1) substances, such as elemental abundances, isotopes, molecules, allotropes, enantiomers, minerals, and their associated properties; (2) objects that are physical features such as mats, fossils including trace-fossils and microbialites (stromatolites), and concretions; and (3) patterns, such as physical three-dimensional or conceptual n-dimensional relationships of physical or chemical phenomena, including patterns of intermolecular abundances of organic homologues, and patterns of stable isotopic abundances between and within compounds. Five key challenges that warrant future exploration by the astrobiology community include the following: (1) examining phenomena at the "right" spatial scales because biosignatures may elude us if not examined with the appropriate instrumentation or modeling approach at that specific scale; (2) identifying the precise context across multiple spatial and temporal scales to understand how tangible biosignatures may or may not be preserved; (3) increasing capability to mine big data sets to reveal relationships, for example, how Earth's mineral diversity may have evolved in conjunction with life; (4) leveraging cyberinfrastructure for data management of biosignature types, characteristics, and classifications; and (5) using three-dimensional to n-D representations of biotic and abiotic models overlain on multiple overlapping spatial and temporal relationships to provide new insights.
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Affiliation(s)
- Marjorie A. Chan
- Department of Geology & Geophysics, University of Utah, Salt Lake City, Utah
| | - Nancy W. Hinman
- Department of Geosciences, University of Montana, Missoula, Montana
| | | | - Keith E. Schubert
- Department of Electrical and Computer Engineering, Baylor University, Waco, Texas
| | - Richard J. Gillams
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
- Electronics and Computer Science, Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Stanley M. Awramik
- Department of Earth Science, University of California, Santa Barbara, Santa Barbara, California
| | - Penelope J. Boston
- NASA Astrobiology Institute, NASA Ames Research Center, Moffett Field, California
| | - Dina M. Bower
- Department of Astronomy, University of Maryland College Park (CRESST), College Park, Maryland
- NASA Goddard Space Flight Center, Greenbelt, Maryland
| | | | - Jack D. Farmer
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona
| | - Tony Z. Jia
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Penelope L. King
- Research School of Earth Sciences, The Australian National University, Canberra, Australia
| | - Robert M. Hazen
- Geophysical Laboratory, Carnegie Institution for Science, Washington, District of Columbia
| | - Richard J. Léveillé
- Department of Earth and Planetary Sciences, McGill University, Montreal, Canada
- Geosciences Department, John Abbott College, Sainte-Anne-de-Bellevue, Canada
| | - Dominic Papineau
- London Centre for Nanotechnology, University College London, London, United Kingdom
- Department of Earth Sciences, University College London, London, United Kingdom
- Centre for Planetary Sciences, University College London, London, United Kingdom
- BioGeology and Environmental Geology State Key Laboratory, School of Earth Sciences, China University of Geosciences, Wuhan, China
| | - Kaitlin R. Rempfert
- Department of Geological Sciences, University of Colorado Boulder, Boulder, Colorado
| | - Mónica Sánchez-Román
- Earth Sciences Department, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - John R. Spear
- Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, Colorado
| | - Gordon Southam
- School of Earth and Environmental Sciences, The University of Queensland, St. Lucia, Queensland, Australia
| | | | - Henderson James Cleaves
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
- Program in Interdisciplinary Studies, Institute for Advanced Study, Princeton, New Jersey
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10
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Pacelli C, Selbmann L, Zucconi L, Coleine C, de Vera JP, Rabbow E, Böttger U, Dadachova E, Onofri S. Responses of the Black Fungus Cryomyces antarcticus to Simulated Mars and Space Conditions on Rock Analogs. Astrobiology 2019; 19:209-220. [PMID: 30067087 DOI: 10.1089/ast.2016.1631] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The BIOMEX (BIOlogy and Mars Experiment) is part of the European Space Agency (ESA) space mission EXPOSE-R2 in Low-Earth Orbit, devoted to exposing microorganisms for 1.5 years to space and simulated Mars conditions on the International Space Station. In preparing this mission, dried colonies of the Antarctic cryptoendolithic black fungus Cryomyces antarcticus CCFEE 515, grown on martian and lunar analog regolith pellets, were subjected to several ground-based preflight tests, Experiment Verification Tests, and Science Verification Tests (SVTs) that were performed to verify (i) the resistance of our model organism to space stressors when grown on extraterrestrial rock analogs and (ii) the possibility of detecting biomolecules as potential biosignatures. Here, the results of the SVTs, the last set of experiments, which were performed in ultraviolet radiation combined with simulated space vacuum or simulated martian conditions, are reported. The results demonstrate that C. antarcticus was able to tolerate the conditions of the SVT experiment, regardless of the substratum in which it was grown. DNA maintained high integrity after treatments and was confirmed as a possible biosignature; melanin, which was chosen to be a target for biosignature detection, was unambiguously detected by Raman spectroscopy.
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Affiliation(s)
- Claudia Pacelli
- 1 Department of Ecological and Biological Sciences (DEB), University of Tuscia, Viterbo, Italy
| | - Laura Selbmann
- 1 Department of Ecological and Biological Sciences (DEB), University of Tuscia, Viterbo, Italy
- 2 Section of Mycology, Italian Antarctic National Museum (MNA), Genoa, Italy
| | - Laura Zucconi
- 1 Department of Ecological and Biological Sciences (DEB), University of Tuscia, Viterbo, Italy
| | - Claudia Coleine
- 1 Department of Ecological and Biological Sciences (DEB), University of Tuscia, Viterbo, Italy
| | - Jean-Pierre de Vera
- 3 Institute of Planetary Research, German Aerospace Center (DLR) Berlin, Berlin, Germany
| | - Elke Rabbow
- 4 German Aerospace Centre, Institute of Aerospace Medicine (DLR), Köln, Germany
| | - Ute Böttger
- 5 Institute of Optical Sensor Systems, German Aerospace Center (DLR) Berlin, Berlin, Germany
| | - Ekaterina Dadachova
- 6 College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Canada
| | - Silvano Onofri
- 1 Department of Ecological and Biological Sciences (DEB), University of Tuscia, Viterbo, Italy
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11
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Blanco Y, de Diego-Castilla G, Viúdez-Moreiras D, Cavalcante-Silva E, Rodríguez-Manfredi JA, Davila AF, McKay CP, Parro V. Effects of Gamma and Electron Radiation on the Structural Integrity of Organic Molecules and Macromolecular Biomarkers Measured by Microarray Immunoassays and Their Astrobiological Implications. Astrobiology 2018; 18:1497-1516. [PMID: 30070898 PMCID: PMC6276817 DOI: 10.1089/ast.2016.1645] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 04/10/2018] [Indexed: 05/20/2023]
Abstract
High-energy ionizing radiation in the form of solar energetic particles and galactic cosmic rays is pervasive on the surface of planetary bodies with thin atmospheres or in space facilities for humans, and it may seriously affect the chemistry and the structure of organic and biological material. We used fluorescent microarray immunoassays to assess how different doses of electron and gamma radiations affect the stability of target compounds such as biological polymers and small molecules (haptens) conjugated to large proteins. The radiation effect was monitored by measuring the loss in the immunoidentification of the target due to an impaired ability of the antibodies for binding their corresponding irradiated and damaged epitopes (the part of the target molecule to which antibodies bind). Exposure to electron radiation alone was more damaging at low doses (1 kGy) than exposure to gamma radiation alone, but this effect was reversed at the highest radiation dose (500 kGy). Differences in the dose-effect immunoidentification patterns suggested that the amount (dose) and not the type of radiation was the main factor for the cumulative damage on the majority of the assayed molecules. Molecules irradiated with both types of radiation showed a response similar to that of the individual treatments at increasing radiation doses, although the pattern obtained with electrons only was the most similar. The calculated radiolysis constant did not show a unique pattern; it rather suggested a different behavior perhaps associated with the unique structure of each molecule. Although not strictly comparable with extraterrestrial conditions because the irradiations were performed under air and at room temperature, our results may contribute to understanding the effects of ionizing radiation on complex molecules and the search for biomarkers through bioaffinity-based systems in planetary exploration.
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Affiliation(s)
- Yolanda Blanco
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain
| | - Graciela de Diego-Castilla
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain
| | - Daniel Viúdez-Moreiras
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain
| | - Erika Cavalcante-Silva
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain
| | | | - Alfonso F. Davila
- Space Science Division, NASA Ames Research Center, Moffett Field, California, USA
| | - Christopher P. McKay
- Space Science Division, NASA Ames Research Center, Moffett Field, California, USA
| | - Victor Parro
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain
- Address correspondence to: Victor Parro, Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Carretera de Ajalvir km 4, Torrejón de Ardoz, Madrid 28850, Spain
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12
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Shkolyar S, Farmer JD. Biosignature Preservation Potential in Playa Evaporites: Impacts of Diagenesis and Implications for Mars Exploration. Astrobiology 2018; 18:1460-1478. [PMID: 30124326 DOI: 10.1089/ast.2018.1849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Assessing biosignature preservation potential (BPP) in ancient habitable environments on Mars is a top NASA priority. We address this goal through the study of Miocene-Pliocene evaporites of the Verde Formation (central Arizona). We assessed the effects of diagenesis on BPP, integrating outcrop-scale observations with six lab analyses: thin-section petrography, X-ray diffraction, Raman spectroscopy, total organic carbon (TOC), electron probe microanalysis (EPMA), and visible to near-infrared (VNIR) reflectance spectroscopy. We recognized five facies and their diagenetic pathways. Two facies included mudstones which contain clusters of displacive growth gypsum (DGG). Early DGG was altered during diagenesis by dissolution forming crystal cavities and later underwent recrystallization, cation substitution, and sulfate dehydration. Another facies was identified by lenticular beds dominated by halite and late diagenetic thenardite (Na2SO4). These pods are overlain by a sequence of interbedded gray and red mudstones which record cyclic oxidation and Fe-oxide cementation. During the Pleistocene, a lacustrine environment developed, accompanied by magnesite cementation of playa mudstones. TOC analyses were used as a proxy for inferring the BPP in each facies. The highest BPP was associated with both red and gray mudstone facies. This study provides a taphonomic framework for playa environments on Earth that record the impacts of diagenesis on BPP, with potential applications to Mars sample return (MSR) missions.
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Affiliation(s)
- Svetlana Shkolyar
- School of Earth and Space Exploration, Arizona State University , Tempe, Arizona
| | - Jack D Farmer
- School of Earth and Space Exploration, Arizona State University , Tempe, Arizona
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13
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de Vera J; The Life Detection Group of BIOMEX/BIOSIGN. A Systematic Way to Life Detection: Combining Field, Lab and Space Research in Low Earth Orbit. In: Cavalazzi B, Westall F, editors. Biosignatures for Astrobiology. Cham: Springer International Publishing; 2019. pp. 111-22. [DOI: 10.1007/978-3-319-96175-0_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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14
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Blanco Y, Gallardo-Carreño I, Ruiz-Bermejo M, Puente-Sánchez F, Cavalcante-Silva E, Quesada A, Prieto-Ballesteros O, Parro V. Critical Assessment of Analytical Techniques in the Search for Biomarkers on Mars: A Mummified Microbial Mat from Antarctica as a Best-Case Scenario. Astrobiology 2017; 17:984-996. [PMID: 29016195 PMCID: PMC5655591 DOI: 10.1089/ast.2016.1467] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 03/20/2017] [Indexed: 05/17/2023]
Abstract
The search for biomarkers of present or past life is one of the major challenges for in situ planetary exploration. Multiple constraints limit the performance and sensitivity of remote in situ instrumentation. In addition, the structure, chemical, and mineralogical composition of the sample may complicate the analysis and interpretation of the results. The aim of this work is to highlight the main constraints, performance, and complementarity of several techniques that have already been implemented or are planned to be implemented on Mars for detection of organic and molecular biomarkers on a best-case sample scenario. We analyzed a 1000-year-old desiccated and mummified microbial mat from Antarctica by Raman and IR (infrared) spectroscopies (near- and mid-IR), thermogravimetry (TG), differential thermal analysis, mass spectrometry (MS), and immunological detection with a life detector chip. In spite of the high organic content (ca. 20% wt/wt) of the sample, the Raman spectra only showed the characteristic spectral peaks of the remaining beta-carotene biomarker and faint peaks of phyllosilicates over a strong fluorescence background. IR spectra complemented the mineralogical information from Raman spectra and showed the main molecular vibrations of the humic acid functional groups. The TG-MS system showed the release of several volatile compounds attributed to biopolymers. An antibody microarray for detecting cyanobacteria (CYANOCHIP) detected biomarkers from Chroococcales, Nostocales, and Oscillatoriales orders. The results highlight limitations of each technique and suggest the necessity of complementary approaches in the search for biomarkers because some analytical techniques might be impaired by sample composition, presentation, or processing. Key Words: Planetary exploration-Life detection-Microbial mat-Life detector chip-Thermogravimetry-Raman spectroscopy-NIR-DRIFTS. Astrobiology 17, 984-996.
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Affiliation(s)
- Yolanda Blanco
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Madrid, Spain
| | | | - Marta Ruiz-Bermejo
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Madrid, Spain
| | | | | | - Antonio Quesada
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Madrid, Spain
- Department of Biology, Universidad Autónoma de Madrid, Madrid, Spain
| | | | - Víctor Parro
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Madrid, Spain
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15
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Leuko S, Bohmeier M, Hanke F, Böettger U, Rabbow E, Parpart A, Rettberg P, de Vera JPP. On the Stability of Deinoxanthin Exposed to Mars Conditions during a Long-Term Space Mission and Implications for Biomarker Detection on Other Planets. Front Microbiol 2017; 8:1680. [PMID: 28966605 PMCID: PMC5605620 DOI: 10.3389/fmicb.2017.01680] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/21/2017] [Indexed: 11/13/2022] Open
Abstract
Outer space, the final frontier, is a hostile and unforgiving place for any form of life as we know it. The unique environment of space allows for a close simulation of Mars surface conditions that cannot be simulated as accurately on the Earth. For this experiment, we tested the resistance of Deinococcus radiodurans to survive exposure to simulated Mars-like conditions in low-Earth orbit for a prolonged period of time as part of the Biology and Mars experiment (BIOMEX) project. Special focus was placed on the integrity of the carotenoid deinoxanthin, which may serve as a potential biomarker to search for remnants of life on other planets. Survival was investigated by evaluating colony forming units, damage inflicted to the 16S rRNA gene by quantitative PCR, and the integrity and detectability of deinoxanthin by Raman spectroscopy. Exposure to space conditions had a strong detrimental effect on the survival of the strains and the 16S rRNA integrity, yet results show that deinoxanthin survives exposure to conditions as they prevail on Mars. Solar radiation is not only strongly detrimental to the survival and 16S rRNA integrity but also to the Raman signal of deinoxanthin. Samples not exposed to solar radiation showed only minuscule signs of deterioration. To test whether deinoxanthin is able to withstand the tested parameters without the protection of the cell, it was extracted from cell homogenate and exposed to high/low temperatures, vacuum, germicidal UV-C radiation, and simulated solar radiation. Results obtained by Raman investigations showed a strong resistance of deinoxanthin against outer space and Mars conditions, with the only exception of the exposure to simulated solar radiation. Therefore, deinoxanthin proved to be a suitable easily detectable biomarker for the search of Earth-like organic pigment-containing life on other planets.
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Affiliation(s)
- Stefan Leuko
- German Aerospace Center, Research Group "Astrobiology", Radiation Biology Department, Institute of Aerospace MedicineKöln, Germany
| | - Maria Bohmeier
- German Aerospace Center, Research Group "Astrobiology", Radiation Biology Department, Institute of Aerospace MedicineKöln, Germany
| | - Franziska Hanke
- German Aerospace Center, Institute of Optical Sensor SystemsBerlin, Germany
| | - Ute Böettger
- German Aerospace Center, Institute of Optical Sensor SystemsBerlin, Germany
| | - Elke Rabbow
- German Aerospace Center, Research Group "Astrobiology", Radiation Biology Department, Institute of Aerospace MedicineKöln, Germany
| | - Andre Parpart
- German Aerospace Center, Research Group "Astrobiology", Radiation Biology Department, Institute of Aerospace MedicineKöln, Germany
| | - Petra Rettberg
- German Aerospace Center, Research Group "Astrobiology", Radiation Biology Department, Institute of Aerospace MedicineKöln, Germany
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Vago JL, Westall F. Habitability on Early Mars and the Search for Biosignatures with the ExoMars Rover. Astrobiology 2017; 17:471-510. [PMID: 31067287 PMCID: PMC5685153 DOI: 10.1089/ast.2016.1533] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 03/05/2017] [Indexed: 05/19/2023]
Abstract
The second ExoMars mission will be launched in 2020 to target an ancient location interpreted to have strong potential for past habitability and for preserving physical and chemical biosignatures (as well as abiotic/prebiotic organics). The mission will deliver a lander with instruments for atmospheric and geophysical investigations and a rover tasked with searching for signs of extinct life. The ExoMars rover will be equipped with a drill to collect material from outcrops and at depth down to 2 m. This subsurface sampling capability will provide the best chance yet to gain access to chemical biosignatures. Using the powerful Pasteur payload instruments, the ExoMars science team will conduct a holistic search for traces of life and seek corroborating geological context information. Key Words: Biosignatures-ExoMars-Landing sites-Mars rover-Search for life. Astrobiology 17, 471-510.
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17
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Verseux C, Baqué M, Cifariello R, Fagliarone C, Raguse M, Moeller R, Billi D. Evaluation of the Resistance of Chroococcidiopsis spp. to Sparsely and Densely Ionizing Irradiation. Astrobiology 2017; 17:118-125. [PMID: 28151689 DOI: 10.1089/ast.2015.1450] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Studying the resistance of cyanobacteria to ionizing radiation provides relevant information regarding astrobiology-related topics including the search for life on Mars, lithopanspermia, and biological life-support systems. Here, we report on the resistance of desert cyanobacteria of the genus Chroococcidiopsis, which were exposed (as part of the STARLIFE series of experiments) in both hydrated and dried states to ionizing radiation with different linear energy transfer values (0.2 to 200 keV/μm). Irradiation with up to 1 kGy of He or Si ions, 2 kGy of Fe ions, 5 kGy of X-rays, or 11.59 kGy of γ rays (60Co) did not eradicate Chroococcidiopsis populations, nor did it induce detectable damage to DNA or plasma membranes. The relevance of these results for astrobiology is briefly discussed. Key Words: Ionizing radiation-Linear energy transfer-Lithopanspermia-Cyanobacterial radioresistance-Chroococcidiopsis-Mars. Astrobiology 17, 118-125.
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Affiliation(s)
- Cyprien Verseux
- 1 Department of Biology, Laboratory of Astrobiology and Molecular Biology of Cyanobacteria from Extreme Environments, University of Rome Tor Vergata , Rome, Italy
| | - Mickael Baqué
- 1 Department of Biology, Laboratory of Astrobiology and Molecular Biology of Cyanobacteria from Extreme Environments, University of Rome Tor Vergata , Rome, Italy
- 2 Astrobiological Laboratories Research Group, Institute of Planetary Research , Management and Infrastructure, German Aerospace Center (DLR), Berlin, Germany
| | - Riccardo Cifariello
- 1 Department of Biology, Laboratory of Astrobiology and Molecular Biology of Cyanobacteria from Extreme Environments, University of Rome Tor Vergata , Rome, Italy
| | - Claudia Fagliarone
- 1 Department of Biology, Laboratory of Astrobiology and Molecular Biology of Cyanobacteria from Extreme Environments, University of Rome Tor Vergata , Rome, Italy
| | - Marina Raguse
- 3 Space Microbiology Research Group, Radiation Biology Department, Institute of Aerospace Medicine , German Aerospace Center (DLR), Cologne, Germany
| | - Ralf Moeller
- 3 Space Microbiology Research Group, Radiation Biology Department, Institute of Aerospace Medicine , German Aerospace Center (DLR), Cologne, Germany
| | - Daniela Billi
- 1 Department of Biology, Laboratory of Astrobiology and Molecular Biology of Cyanobacteria from Extreme Environments, University of Rome Tor Vergata , Rome, Italy
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18
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Smith JP, Smith FC, Booksh KS. Spatial and spectral resolution of carbonaceous material from hematite (α-Fe2O3) using multivariate curve resolution-alternating least squares (MCR-ALS) with Raman microspectroscopic mapping: implications for the search for life on Mars. Analyst 2017; 142:3140-3156. [DOI: 10.1039/c7an00481h] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report a novel application of multivariate analysis with Raman microspectroscopic mapping to enhance the search for life on Mars.
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Affiliation(s)
- Joseph P. Smith
- Department of Chemistry & Biochemistry
- University of Delaware
- Newark
- USA
| | - Frank C. Smith
- Department of Geological Sciences
- University of Delaware
- Newark
- USA
| | - Karl S. Booksh
- Department of Chemistry & Biochemistry
- University of Delaware
- Newark
- USA
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19
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Baqué M, Verseux C, Böttger U, Rabbow E, de Vera JPP, Billi D. Preservation of Biomarkers from Cyanobacteria Mixed with Mars-Like Regolith Under Simulated Martian Atmosphere and UV Flux. ORIGINS LIFE EVOL B 2016; 46:289-310. [PMID: 26530341 DOI: 10.1007/s11084-015-9467-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 08/27/2015] [Indexed: 02/05/2023]
Abstract
The space mission EXPOSE-R2 launched on the 24th of July 2014 to the International Space Station is carrying the BIOMEX (BIOlogy and Mars EXperiment) experiment aimed at investigating the endurance of extremophiles and stability of biomolecules under space and Mars-like conditions. In order to prepare the analyses of the returned samples, ground-based simulations were carried out in Planetary and Space Simulation facilities. During the ground-based simulations, Chroococcidiopsis cells mixed with two Martian mineral analogues (phyllosilicatic and sulfatic Mars regolith simulants) were exposed to a Martian simulated atmosphere combined or not with UV irradiation corresponding to the dose received during a 1-year-exposure in low Earth orbit (or half a Martian year on Mars). Cell survival and preservation of potential biomarkers such as photosynthetic and photoprotective pigments or DNA were assessed by colony forming ability assays, confocal laser scanning microscopy, Raman spectroscopy and PCR-based assays. DNA and photoprotective pigments (carotenoids) were detectable after simulations of the space mission (570 MJ/m(2) of UV 200-400 nm irradiation and Martian simulated atmosphere), even though signals were attenuated by the treatment. The fluorescence signal from photosynthetic pigments was differently preserved after UV irradiation, depending on the thickness of the samples. UV irradiation caused a high background fluorescence of the Martian mineral analogues, as revealed by Raman spectroscopy. Further investigation will be needed to ensure unambiguous identification and operations of future Mars missions. However, a 3-month exposure to a Martian simulated atmosphere showed no significant damaging effect on the tested cyanobacterial biosignatures, pointing out the relevance of the latter for future investigations after the EXPOSE-R2 mission. Data gathered during the ground-based simulations will contribute to interpret results from space experiments and guide our search for life on Mars.
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Affiliation(s)
- Mickael Baqué
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | - Cyprien Verseux
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | - Ute Böttger
- German Aerospace Center (DLR), Institute of Planetary Research, Berlin, Germany
| | - Elke Rabbow
- Radiation Biology Department, German Aerospace Center (DLR), Institute of Aerospace Medicine, Köln, Germany
| | | | - Daniela Billi
- Department of Biology, University of Rome Tor Vergata, Rome, Italy.
- Dipartimento di Biologia, Università di Roma "Tor Vergata", Rome, Italy.
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Farci D, Slavov C, Tramontano E, Piano D. The S-layer Protein DR_2577 Binds Deinoxanthin and under Desiccation Conditions Protects against UV-Radiation in Deinococcus radiodurans. Front Microbiol 2016; 7:155. [PMID: 26909071 PMCID: PMC4754619 DOI: 10.3389/fmicb.2016.00155] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 01/29/2016] [Indexed: 11/13/2022] Open
Abstract
Deinococcus radiodurans has the puzzling ability to withstand over a broad range of extreme conditions including high doses of ultraviolet radiation and deep desiccation. This bacterium is surrounded by a surface layer (S-layer) built of a regular repetition of several proteins, assembled to form a paracrystalline structure. Here we report that the deletion of a main constituent of this S-layer, the gene DR_2577, causes a decrease in the UVC resistance, especially in desiccated cells. Moreover, we show that the DR_2577 protein binds the carotenoid deinoxanthin, a strong protective antioxidant specific of this bacterium. A further spectroscopical characterization of the deinoxanthin-DR_2577 complex revealed features which could suggest a protective role of DR_2577. We propose that, especially under desiccation, the S-layer shields the bacterium from incident ultraviolet light and could behave as a first lane of defense against UV radiation.
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Affiliation(s)
- Domenica Farci
- Laboratory of Plant Physiology and Photobiology, Department of Life and Environmental Sciences, University of Cagliari Cagliari, Italy
| | - Chavdar Slavov
- Department of Physical Chemistry, Institute of Physical and Theoretical Chemistry Frankfurt am Main, Germany
| | - Enzo Tramontano
- Laboratory of Molecular Virology, Department of Life and Environmental Sciences, University of Cagliari Cagliari, Italy
| | - Dario Piano
- Laboratory of Plant Physiology and Photobiology, Department of Life and Environmental Sciences, University of CagliariCagliari, Italy; International Institute of Molecular and Cell BiologyWarsaw, Poland
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Harris LV, Hutchinson IB, Ingley R, Marshall CP, Olcott Marshall A, Edwards HG. Selection of Portable Spectrometers for Planetary Exploration: A Comparison of 532 nm and 785 nm Raman Spectroscopy of Reduced Carbon in Archean Cherts. Astrobiology 2015; 15:420-9. [PMID: 26060980 PMCID: PMC4490632 DOI: 10.1089/ast.2014.1220] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Knowledge and understanding of the martian environment has advanced greatly over the past two decades, beginning with NASA's return to the surface of Mars with the Pathfinder mission and its rover Sojourner in 1997 and continuing today with data being returned by the Curiosity rover. Reduced carbon, however, is yet to be detected on the martian surface, despite its abundance in meteorites originating from the planet. If carbon is detected on Mars, it could be a remnant of extinct life, although an abiotic source is much more likely. If the latter is the case, environmental carbonaceous material would still provide a source of carbon that could be utilized by microbial life for biochemical synthesis and could therefore act as a marker for potential habitats, indicating regions that should be investigated further. For this reason, the detection and characterization of reduced or organic carbon is a top priority for both the ESA/Roscosmos ExoMars rover, currently due for launch in 2018, and for NASA's Mars 2020 mission. Here, we present a Raman spectroscopic study of Archean chert Mars analog samples from the Pilbara Craton, Western Australia. Raman spectra were acquired with a flight-representative 532 nm instrument and a 785 nm instrument with similar operating parameters. Reduced carbon was successfully detected with both instruments; however, its Raman bands were detected more readily with 785 nm excitation, and the corresponding spectra exhibited superior signal-to-noise ratios and reduced background levels.
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Affiliation(s)
- Liam V. Harris
- Department of Physics and Astronomy, University of Leicester, Leicester, UK
| | - Ian B. Hutchinson
- Department of Physics and Astronomy, University of Leicester, Leicester, UK
| | - Richard Ingley
- Department of Physics and Astronomy, University of Leicester, Leicester, UK
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Al-Beloshei NE, Al-Awadhi H, Al-Khalaf RA, Afzal M. A comparative study of fatty acid profile and formation of biofilm inGeobacillus gargensisexposed to variable abiotic stress. Can J Microbiol 2015; 61:48-59. [DOI: 10.1139/cjm-2014-0615] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Understanding bacterial fatty acid (FA) profile has a great taxonomic significance as well as clinical importance for diagnosis issues. Both the composition and nature of membrane FAs change under different nutritional, biotic and (or) abiotic stresses, and environmental stress. Bacteria produce both odd-carbon as well as branched-chain fatty acids (BCFAs). This study was designed to examine the effect of abiotic pressure, including salinity, temperature, pH, and oxinic stress on the growth, development, and FA profile in thermophilic Geobacillus gargensis. Under these stresses, 3 parametric ratios, 2-methyl fatty acids/3-methyl fatty acids (iso-/anteiso-FAs), BCFAs/straight-chain saturated fatty acids (SCSFA), and SCSFAs/straight-chain unsaturated fatty acids (SCUFA), in addition to total lipids affected by variable stresses were measured. Our results indicate that the ratio of total iso-/anteiso-FAs increased at the acidic pH range of 4.1–5.2 and decreased with increasing pH. The reverse was true for salt stress when iso-/anteiso-FAs ratio increased with salt concentration. The BCFAs/SCSFAs and SCSFAs/SCUFAs ratios increased at neutral and alkaline pH and high salt concentration, reduced incubation time, and comparatively high temperature (55–65 °C) of the growth medium. The bacterial total lipid percentage deceased with increasing salt concentration, incubation period, but it increased with temperature. The formation of extracellular polymeric substances was observed under all stress conditions and with the addition of sodium dodecyl sulfate (2 and 5 mmol/L) to the growth medium. The membrane phospholipid composition of the bacterium was analyzed by thin-layer chromatography.
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Affiliation(s)
| | - Husain Al-Awadhi
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait
| | - Rania A. Al-Khalaf
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait
| | - Mohammad Afzal
- Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait
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Camacho-Córdova DI, Camacho-Ruíz RM, Córdova-López JA, Cervantes-Martínez J. Estimation of bacterioruberin by Raman spectroscopy during the growth of halophilic archaeon Haloarcula marismortui. Appl Opt 2014; 53:7470-7475. [PMID: 25402913 DOI: 10.1364/ao.53.007470] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Halophilic archaea are interesting microorganisms that produce low biomass and metabolites, complicating their quantification. Raman spectroscopy (RS) is a powerful technique, which requires small samples, attractive for using in archaeal research. The objective of this work was the estimation of bacterioruberin content along with Haloarcula marismortui growth and their correlation with biomass concentration. RS was used to detect characteristic bands of bacterioruberin (vibrational modes C═CH, C─C, and C═C) in H. marismortui culture samples. The intensity of Raman spectra in bacterioruberin and the biomass concentration were adequately correlated. The highest production of bacterioruberin occurred at 60 h. RS is revealed as a reliable technique for the estimation of bacterioruberin in the biomass of H. marismortui, which could be considered as a promising qualitative and quantitative technique to assay metabolites in cell cultures.
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Abstract
Raman spectroscopy is a rapid nondestructive technique providing spectroscopic and structural information on both organic and inorganic molecular compounds. Extensive applications for the method in the characterization of pigments have been found. Due to the high sensitivity of Raman spectroscopy for the detection of chlorophylls, carotenoids, scytonemin, and a range of other pigments found in the microbial world, it is an excellent technique to monitor the presence of such pigments, both in pure cultures and in environmental samples. Miniaturized portable handheld instruments are available; these instruments can be used to detect pigments in microbiological samples of different types and origins under field conditions.
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Abstract
Beginning from two plausible starting points-an uninhabited or inhabited Mars-this paper discusses the possible trajectories of martian habitability over time. On an uninhabited Mars, the trajectories follow paths determined by the abundance of uninhabitable environments and uninhabited habitats. On an inhabited Mars, the addition of a third environment type, inhabited habitats, results in other trajectories, including ones where the planet remains inhabited today or others where planetary-scale life extinction occurs. By identifying different trajectories of habitability, corresponding hypotheses can be described that allow for the various trajectories to be disentangled and ultimately a determination of which trajectory Mars has taken and the changing relative abundance of its constituent environments.
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Affiliation(s)
- Charles S Cockell
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh , Edinburgh, UK
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Varnali T, Edwards HGM. Reduced and oxidised scytonemin: theoretical protocol for Raman spectroscopic identification of potential key biomolecules for astrobiology. Spectrochim Acta A Mol Biomol Spectrosc 2014; 117:72-77. [PMID: 23981417 DOI: 10.1016/j.saa.2013.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Revised: 07/23/2013] [Accepted: 08/02/2013] [Indexed: 06/02/2023]
Abstract
Scytonemin is an important UV-radiation protective biomolecule synthesised by extremophilic cyanobacteria in stressed terrestrial environments. Scytonemin and its reduced form have been both isolated experimentally and the Raman spectrum for scytonemin has been assigned and characterised experimentally both in extracts and in living extremophilic cyanobacterial colonies. Scytonemin is recognised as a key biomarker molecule for terrestrial organisms in stressed environments. We propose a new, theoretically plausible structure for oxidised scytonemin which has not been mentioned in the literature hitherto. DFT calculations for scytonemin, reduced scytonemin and the new structure modelled and proposed for oxidised scytonemin are reported along with their Raman spectroscopic data and λmax UV-absorption data obtained theoretically. Comparison of the vibrational spectroscopic assignments allows the three forms of scytonemin to be detected and identified and assist not only in the clarification of the major features in the experimentally observed Raman spectral data for the parent scytonemin but also support a protocol proposed for their analytical discrimination. The results of this study provide a basis for the search for molecules of this type in future astrobiological missions of exploration and the search for extinct and extant life terrestrially.
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Affiliation(s)
- Tereza Varnali
- Department of Chemistry, Faculty of Arts and Sciences, Bogazici University, Bebek 34342, Istanbul, Turkey.
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Hassler DM, Zeitlin C, Wimmer-Schweingruber RF, Ehresmann B, Rafkin S, Eigenbrode JL, Brinza DE, Weigle G, Böttcher S, Böhm E, Burmeister S, Guo J, Köhler J, Martin C, Reitz G, Cucinotta FA, Kim MH, Grinspoon D, Bullock MA, Posner A, Gómez-Elvira J, Vasavada A, Grotzinger JP. Mars' surface radiation environment measured with the Mars Science Laboratory's Curiosity rover. Science 2013; 343:1244797. [PMID: 24324275 DOI: 10.1126/science.1244797] [Citation(s) in RCA: 219] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.
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Varnali T, Edwards HGM. Theoretical study of novel complexed structures for methoxy derivatives of scytonemin: potential biomarkers in iron-rich stressed environments. Astrobiology 2013; 13:861-869. [PMID: 23992252 DOI: 10.1089/ast.2013.0980] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Scytonemin is a cyanobacterial sheath pigment with potent UV (UVA, UVB, and UVC) absorbing properties. Di- and tetramethoxy derivatives of scytonemin have also been found and described in the literature. The importance of these biomolecules is their photoprotective function, which is one of the major survival strategies adopted by extremophiles in environmentally stressed conditions. Also, iron compounds [particularly iron(III) oxides] offer an additional UV-protecting facility to subsurface endolithic biological colonization; hence, banded iron formations (accompanied by zones of depletion of iron) in rock matrices have attracted attention with special interest in the method of transportation of iron compounds through the rock. Di- and tetramethoxyscytonemin and their iron(III) complexes have been modeled and studied computationally by using density functional theory calculations at the level of B3LYP/6-31G** methodology. We propose new structures that could feature in survival strategy and facilitate the movement of iron through the rock especially for iron-rich stressed terrestrial environments exemplified by the Río Tinto system with the added potential of subsurface Mars exploration. This study represents a continuation of our previous work on scytonemin. The calculated Raman spectra of the proposed iron complexes are compared with those of their parent compounds and discussed in relation to structural changes effected in the parent ligand upon complexation. This information leads to new insights to be gained by experimental Raman spectroscopists and the characterization of spectroscopic biosignatures for the database being compiled for the remote Raman analytical interrogation of the martian surface and subsurface being proposed for the ESA ExoMars mission planned for launch in 2018.
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Affiliation(s)
- Tereza Varnali
- 1 Department of Chemistry, Bogazici University , Istanbul, Turkey
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Jorge-Villar SE, Edwards HG. Microorganism response to stressed terrestrial environments: a Raman spectroscopic perspective of extremophilic life strategies. Life (Basel) 2013; 3:276-94. [PMID: 25371344 DOI: 10.3390/life3010276] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/30/2013] [Accepted: 02/17/2013] [Indexed: 11/24/2022] Open
Abstract
Raman spectroscopy is a valuable analytical technique for the identification of biomolecules and minerals in natural samples, which involves little or minimal sample manipulation. In this paper, we evaluate the advantages and disadvantages of this technique applied to the study of extremophiles. Furthermore, we provide a review of the results published, up to the present point in time, of the bio- and geo-strategies adopted by different types of extremophile colonies of microorganisms. We also show the characteristic Raman signatures for the identification of pigments and minerals, which appear in those complex samples.
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