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Daniela Billi - One of the best experts on this subject based on the ideXlab platform.
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Biomarker Preservation and Survivability Under Extreme Dryness and Mars-Like UV Flux of a Desert Cyanobacterium Capable of Trehalose and Sucrose Accumulation
Frontiers in Astronomy and Space Sciences, 2020Co-Authors: Claudia Fagliarone, Mickael Baqué, Jean-pierre De Vera, Alessandro Napoli, Salvatore Chiavarini, Daniela BilliAbstract:Unravelling how long life can persist under extreme dryness and what kind of environmental extremes can be faced by dried microorganisms, is relevant to understand Mars habitability and to search for life on planets with transient liquid water availability. Since trehalose and sucrose stabilize dried anhydrobiotes, an in silico survey of the genome of the desert cyanobacterium Chroococcidiopsis sp. CCMEE 029 was performed to identify pathways for trehalose and sucrose biosynthesis. The expression of the identified genes was induced in response to desiccation and trehalose and sucrose accumulation was detected in dried cells. This adaptation strategy enabled viability and biomarker permanence under extreme dryness and Mars-like UV flux. Chroococcidiopsis survivors were scored in 7-year dried biofilms mixed with phyllosilicatic Mars regolith simulant and exposed to 5.5 x 103 kJ/m2 of a Mars-like UV flux. No survivors occurred after exposure to 5.5 x 105 kJ/m2, although in dead cells, photosynthetic pigments and nucleic acids, both DNA and RNA, were still detectable. This suggested that dried biofilms mixed with phyllosilicatic Martian regolith simulant are suitable candidates to identify biosignatures embedded in planetary analogue minerals as planned in the future BioSigN (BioSignatures and habitable Niches) space mission to be performed outside the International Space Station.
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Dried Biofilms of Desert Strains of Chroococcidiopsis Survived Prolonged Exposure to Space and Mars-like Conditions in Low Earth Orbit.
Astrobiology, 2019Co-Authors: Daniela Billi, Mickael Baqué, Cyprien Verseux, Claudia Mosca, Claudia Fagliarone, Elke Rabbow, Clelia Staibano, Petra RettbergAbstract:Abstract Dried biofilms and dried multilayered planktonic counterparts obtained from three desert strains of Chroococcidiopsis were exposed to low Earth conditions by using the EXPOSE-R2 facility o...
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A Desert Cyanobacterium under Simulated Mars-like Conditions in Low Earth Orbit: Implications for the Habitability of Mars
Astrobiology, 2019Co-Authors: Daniela Billi, Mickael Baqué, Cyprien Verseux, Claudia Fagliarone, Alessandro Napoli, Jean-pierre De VeraAbstract:Abstract In the ESA space experiment BIOMEX (BIOlogy and Mars EXperiment), dried Chroococcidiopsis cells were exposed to Mars-like conditions during the EXPOSE-R2 mission on the International Space...
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Avoidance of protein oxidation correlates with the desiccation and radiation resistance of hot and cold desert strains of the cyanobacterium Chroococcidiopsis
Extremophiles, 2017Co-Authors: Claudia Fagliarone, Mickael Baqué, Cyprien Verseux, Claudia Mosca, Annick Wilmotte, Ilaria Ubaldi, Daniela BilliAbstract:To investigate the relationship between desiccation and the extent of protein oxidation in desert strains of Chroococcidiopsis a selection of 10 isolates from hot and cold deserts and the terrestrial cyanobacterium Chroococcidiopsis thermalis sp. PCC 7203 were exposed to desiccation (air-drying) and analyzed for survival. Strain CCMEE 029 from the Negev desert and the aquatic cyanobacterium Synechocystis sp. PCC 6803 were further investigated for protein oxidation after desiccation (drying over silica gel), treatment with H_2O_2 up to 1 M and exposure to γ-rays up to 25 kGy. Then a selection of desert strains of Chroococcidiopsis with different survival rates after prolonged desiccation, as well as Synechocystis sp. PCC 6803 and Chroococcidiopsis thermalis sp. PCC 7203, were analyzed for protein oxidation after treatment with 10 and 100 mM of H_2O_2. Results suggest that in the investigated strains a tight correlation occurs between desiccation and radiation tolerance and avoidance of protein oxidation.
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Unravelling the secret of the resistance of desert strains of Chroococcidiopsis to desiccation and radiation
2017Co-Authors: Daniela Billi, Mickael Baqué, Fagliarone, Cyprien Verseux, Claudia Mosca, Annick WilmotteAbstract:Chroococcidiopsis is a unicellular cyanobacterial genus that is growing in extreme dry conditions, either in low or high temperatures. At the lower end of the spectrum, they live as cryptoendoliths in rocks of the Mc Murdo Dry Valleys in Antarctica where they were discovered by Imre Friedmann, while at the higher end, they grow as hypoliths/endoliths in hot deserts, e.g. Negev, Gobi, Atacama (Friedman, 1980). The capacity of desert strains of Chroococcidiopsis to stabilize their sub-cellular organization is so efficient that, when dried, they can cope with simulated space and Martian conditions (Billi et al 2011 ; Baque et al. 2013a) as well as with high doses of ionizing and UV radiations (Verseux et al. 2017 ; Baque et al. 2013b). Since it is known for radiation/desiccation tolerant bacteria that the capability to avoid protein oxidation is critical to cope with such stressors (Frederickson et al. 2008; Daly et al. 2007), the present study investigates the protein oxidation after prolonged desiccation, irradiation with gamma-rays up to 25kGy and treatment with hydrogen peroxide in a selection of desert Chroococcidiopsis isolates, including 2 Antarctic strains: CCMEE134 and CMEE171 isolated from Beacon Valley and University Valley, respectively (Mc Murdo Dry Valleys). A tight correlation was observed between the desiccation and radiation tolerance of the investigated desert strains and the absence of oxidative damage to proteins. The efficiency of the antioxidant systems of the desert strains of Chroococcidiopsis was highlighted also by the lack of protein carbonylation until treatment with 1M of oxygen peroxide. The phylogenetic analysis of the investigated 11 desert strains of Chroococcidiopsis is reported. References Baque, M. et al. 2013a. Biofilm and planktonic lifestyles differently support the resistance of the desert cyanobacterium Chroococcidiopsis under space and Martian simulations. Origin of Life and Evolution of Biospheres 3,377-89. Baque, M. et al. 2013b. Endurance of the endolithic desert cyanobacterium Chroococcidiopsis under UVC radiation. Extremophiles 17,161-169. Billi, D. et 2011. Damage escape and repair in dried Chroococcidiopsis spp. from hot and cold deserts exposed to simulated space and Martian conditions. Astrobiology 11,65-73. Daly, M.J. et al., 2007. Protein oxidation implicated as the primary determinant of bacterial radioresistance. PLoS Biology, 5(4), p.e92. Fredrickson, J.K. et al. (2008) Protein oxidation: key to bacterial desiccation resistance? Int J Syst Evol Microbiol 2:393-403 Friedmann, E.I. 1980. Endolithic microbial life in hot and cold deserts. Origins of Life and Evolution of Biospheres10, 223-235. Verseux, C. et al. 2017. Evaluation of the resistance of Chroococcidiopsis spp. to sparsely and densely ionizing irradiation. Astrobiology 17,118-125 This work was supported by the Italian National Antarctic Research Program This work is dedicated to the memory of Roseli Ocampo-Friedmann and E. Imre Friedmann who pioneered the research on Chroococcidiopsis and life in extreme environments
Charles S Cockell - One of the best experts on this subject based on the ideXlab platform.
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Liquid Water Restricts Habitability in Extreme Deserts
Astrobiology, 2017Co-Authors: Charles S Cockell, Hanna Landenmark, Toby Samuels, Rebecca Siddall, Sarah Brown, Jennifer WadsworthAbstract:Abstract Liquid water is a requirement for biochemistry, yet under some circumstances it is deleterious to life. Here, we show that liquid water reduces the upper temperature survival limit for two extremophilic photosynthetic microorganisms (Gloeocapsa and Chroococcidiopsis spp.) by greater than 40°C under hydrated conditions compared to desiccated conditions. Under hydrated conditions, thermal stress causes protein inactivation as shown by the fluorescein diacetate assay. The presence of water was also found to enhance the deleterious effects of freeze-thaw in Chroococcidiopsis sp. In the presence of water, short-wavelength UV radiation more effectively kills Gloeocapsa sp. colonies, which we hypothesize is caused by factors including the greater penetration of UV radiation into hydrated colonies compared to desiccated colonies. The data predict that deserts where maximum thermal stress or irradiation occurs in conjunction with the presence of liquid water may be less habitable to some organisms than mo...
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exposure of phototrophs to 548 days in low earth orbit microbial selection pressures in outer space and on early earth
The ISME Journal, 2011Co-Authors: Charles S Cockell, Elke Rabbow, Petra Rettberg, Karen OlssonfrancisAbstract:An epilithic microbial community was launched into low Earth orbit, and exposed to conditions in outer space for 548 days on the European Space Agency EXPOSE-E facility outside the International Space Station. The natural phototroph biofilm was augmented with akinetes of Anabaena cylindrica and vegetative cells of Nostoc commune and Chroococcidiopsis. In space-exposed dark controls, two algae (Chlorella and Rosenvingiella spp.), a cyanobacterium (Gloeocapsa sp.) and two bacteria associated with the natural community survived. Of the augmented organisms, cells of A. cylindrica and Chroococcidiopsis survived, but no cells of N. commune. Only cells of Chroococcidiopsis were cultured from samples exposed to the unattenuated extraterrestrial ultraviolet (UV) spectrum (>110 nm or 200 nm). Raman spectroscopy and bright-field microscopy showed that under these conditions the surface cells were bleached and their carotenoids were destroyed, although cell morphology was preserved. These experiments demonstrate that outer space can act as a selection pressure on the composition of microbial communities. The results obtained from samples exposed to >200 nm UV (simulating the putative worst-case UV exposure on the early Earth) demonstrate the potential for epilithic colonization of land masses during that time, but that UV radiation on anoxic planets can act as a strong selection pressure on surface-dwelling organisms. Finally, these experiments have yielded new phototrophic organisms of potential use in biomass and oxygen production in space exploration.
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Damage escape and repair in dried Chroococcidiopsis spp. from hot and cold deserts exposed to simulated space and martian conditions.
Astrobiology, 2011Co-Authors: Daniela Billi, Charles S Cockell, Emanuela Viaggiu, Elke Rabbow, Gerda Horneck, Silvano OnofriAbstract:Abstract The cyanobacterium Chroococcidiopsis, overlain by 3 mm of Antarctic sandstone, was exposed as dried multilayers to simulated space and martian conditions. Ground-based experiments were conducted in the context of Lichens and Fungi Experiments (EXPOSE-E mission, European Space Agency), which were performed to evaluate, after 1.5 years on the International Space Station, the survival of cyanobacteria (Chroococcidiopsis), lichens, and fungi colonized on Antarctic rock. The survival potential and the role played by protection and repair mechanisms in the response of dried Chroococcidiopsis cells to ground-based experiments were both investigated. Different methods were employed, including evaluation of the colony-forming ability, single-cell analysis of subcellular integrities based on membrane integrity molecular and redox probes, evaluation of the photosynthetic pigment autofluorescence, and assessment of the genomic DNA integrity with a PCR-based assay. Desiccation survivors of strain CCMEE 123 (c...
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Use of cyanobacteria for in-situ resource use in space applications
Planetary and Space Science, 2010Co-Authors: Karen Olsson-francis, Charles S CockellAbstract:The regolith of other planetary bodies, such as the Moon and Mars, is rich in inorganic elements that could potentially be exploited for space applications. Lithotrophic microorganisms that are capable of utilising rocks as a growth substrate, and facilitate the extraction of elements, are ideal candidates for in-situ resource use. Of particular interest are the cyanobacteria, which have been suggested for applications, such as oxygen, fuel and biomass production, nutrient acquisition, and feedstock provisions. In this study, Gloeocapsa strain OU_20, isolated from a rock-dwelling community exposed to low Earth orbit; Leptolyngbya strain OU_13 and Phormidium strain OU_10, both isolated from a rock-dwelling community exposed to Mars simulated conditions; Chroococcidiopsis 029; Arthrospira platensis; Synechococcus elongatus; and Anabaena cylindrica, were examined as potential organisms for space in-situ resource use. Volcanic rocks, including basalt (low in SiO2) analogous to martian and lunar basalt, rhyolite (high in SiO2), and anorthosite analogous to lunar regolith were used as growth substrates. The growth rate and rock dissolution were significantly lower with rhyolite demonstrating the importance of silica content in defining the potential for in-situ resource use. Biological weathering resulted in the release of bio-essential elements from the rock matrix, highlighting the potential of cyanobacteria for applications such as bio-mining and nutrient acquisition, on other planets. A. cylindrica produced the maximum biomass with the three rock-types and the optimal value was obtained with the basalt. Exposure experiments demonstrated that A. cylindrica, Chroococcidiopsis 029, Gloeocapsa strain OU_20, Phormidium strain OU_10, and Leptolyngbya strain OU_13 were able to survive 28 days of exposure to desiccation and Mars simulated conditions, which is beneficial in case of system malfunction and for storage. The results from this study indicate that cyanobacteria can potentially be used for in-situ planetary resource acquisition.
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Microbial rock inhabitants survive hypervelocity impacts on Mars-like host planets: First phase of lithopanspermia experimentally tested
Astrobiology, 2008Co-Authors: Gerda Horneck, Charles S Cockell, Ralf Moeller, Dieter Stöffler, Sieglinde Ott, Ulrich Hornemann, C. Meyer, Jean-pierre De Vera, Jörg Fritz, Sara SchadeAbstract:ABSTRACT The scenario of lithopanspermia describes the viable transport of microorganisms via meteorites. To test the first step of lithopanspermia, i.e., the impact ejection from a planet, systematic shock recovery experiments within a pressure range observed in martian meteorites (5–50 GPa) were performed with dry layers of microorganisms (spores of Bacillus subtilis, cells of the endolithic cyanobacterium Chroococcidiopsis, and thalli and ascocarps of the lichen Xanthoria elegans) sandwiched between gabbro discs (martian analogue rock). Actual shock pressures were determined by refractive index measurements and Raman spectroscopy, and shock temperature profiles were calculated. Pressure-effect curves were constructed for survival of B. subtilis spores and Chroococcidiopsis cells from the number of colony-forming units, and for vitality of the photobiont and mycobiont of Xanthoria elegans from confocal laser scanning microscopy after live/dead staining (FUN-I). A vital launch window for the transport of...
Mickael Baqué - One of the best experts on this subject based on the ideXlab platform.
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Biomarker Preservation and Survivability Under Extreme Dryness and Mars-Like UV Flux of a Desert Cyanobacterium Capable of Trehalose and Sucrose Accumulation
Frontiers in Astronomy and Space Sciences, 2020Co-Authors: Claudia Fagliarone, Mickael Baqué, Jean-pierre De Vera, Alessandro Napoli, Salvatore Chiavarini, Daniela BilliAbstract:Unravelling how long life can persist under extreme dryness and what kind of environmental extremes can be faced by dried microorganisms, is relevant to understand Mars habitability and to search for life on planets with transient liquid water availability. Since trehalose and sucrose stabilize dried anhydrobiotes, an in silico survey of the genome of the desert cyanobacterium Chroococcidiopsis sp. CCMEE 029 was performed to identify pathways for trehalose and sucrose biosynthesis. The expression of the identified genes was induced in response to desiccation and trehalose and sucrose accumulation was detected in dried cells. This adaptation strategy enabled viability and biomarker permanence under extreme dryness and Mars-like UV flux. Chroococcidiopsis survivors were scored in 7-year dried biofilms mixed with phyllosilicatic Mars regolith simulant and exposed to 5.5 x 103 kJ/m2 of a Mars-like UV flux. No survivors occurred after exposure to 5.5 x 105 kJ/m2, although in dead cells, photosynthetic pigments and nucleic acids, both DNA and RNA, were still detectable. This suggested that dried biofilms mixed with phyllosilicatic Martian regolith simulant are suitable candidates to identify biosignatures embedded in planetary analogue minerals as planned in the future BioSigN (BioSignatures and habitable Niches) space mission to be performed outside the International Space Station.
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Dried Biofilms of Desert Strains of Chroococcidiopsis Survived Prolonged Exposure to Space and Mars-like Conditions in Low Earth Orbit.
Astrobiology, 2019Co-Authors: Daniela Billi, Mickael Baqué, Cyprien Verseux, Claudia Mosca, Claudia Fagliarone, Elke Rabbow, Clelia Staibano, Petra RettbergAbstract:Abstract Dried biofilms and dried multilayered planktonic counterparts obtained from three desert strains of Chroococcidiopsis were exposed to low Earth conditions by using the EXPOSE-R2 facility o...
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A Desert Cyanobacterium under Simulated Mars-like Conditions in Low Earth Orbit: Implications for the Habitability of Mars
Astrobiology, 2019Co-Authors: Daniela Billi, Mickael Baqué, Cyprien Verseux, Claudia Fagliarone, Alessandro Napoli, Jean-pierre De VeraAbstract:Abstract In the ESA space experiment BIOMEX (BIOlogy and Mars EXperiment), dried Chroococcidiopsis cells were exposed to Mars-like conditions during the EXPOSE-R2 mission on the International Space...
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Avoidance of protein oxidation correlates with the desiccation and radiation resistance of hot and cold desert strains of the cyanobacterium Chroococcidiopsis
Extremophiles, 2017Co-Authors: Claudia Fagliarone, Mickael Baqué, Cyprien Verseux, Claudia Mosca, Annick Wilmotte, Ilaria Ubaldi, Daniela BilliAbstract:To investigate the relationship between desiccation and the extent of protein oxidation in desert strains of Chroococcidiopsis a selection of 10 isolates from hot and cold deserts and the terrestrial cyanobacterium Chroococcidiopsis thermalis sp. PCC 7203 were exposed to desiccation (air-drying) and analyzed for survival. Strain CCMEE 029 from the Negev desert and the aquatic cyanobacterium Synechocystis sp. PCC 6803 were further investigated for protein oxidation after desiccation (drying over silica gel), treatment with H_2O_2 up to 1 M and exposure to γ-rays up to 25 kGy. Then a selection of desert strains of Chroococcidiopsis with different survival rates after prolonged desiccation, as well as Synechocystis sp. PCC 6803 and Chroococcidiopsis thermalis sp. PCC 7203, were analyzed for protein oxidation after treatment with 10 and 100 mM of H_2O_2. Results suggest that in the investigated strains a tight correlation occurs between desiccation and radiation tolerance and avoidance of protein oxidation.
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Unravelling the secret of the resistance of desert strains of Chroococcidiopsis to desiccation and radiation
2017Co-Authors: Daniela Billi, Mickael Baqué, Fagliarone, Cyprien Verseux, Claudia Mosca, Annick WilmotteAbstract:Chroococcidiopsis is a unicellular cyanobacterial genus that is growing in extreme dry conditions, either in low or high temperatures. At the lower end of the spectrum, they live as cryptoendoliths in rocks of the Mc Murdo Dry Valleys in Antarctica where they were discovered by Imre Friedmann, while at the higher end, they grow as hypoliths/endoliths in hot deserts, e.g. Negev, Gobi, Atacama (Friedman, 1980). The capacity of desert strains of Chroococcidiopsis to stabilize their sub-cellular organization is so efficient that, when dried, they can cope with simulated space and Martian conditions (Billi et al 2011 ; Baque et al. 2013a) as well as with high doses of ionizing and UV radiations (Verseux et al. 2017 ; Baque et al. 2013b). Since it is known for radiation/desiccation tolerant bacteria that the capability to avoid protein oxidation is critical to cope with such stressors (Frederickson et al. 2008; Daly et al. 2007), the present study investigates the protein oxidation after prolonged desiccation, irradiation with gamma-rays up to 25kGy and treatment with hydrogen peroxide in a selection of desert Chroococcidiopsis isolates, including 2 Antarctic strains: CCMEE134 and CMEE171 isolated from Beacon Valley and University Valley, respectively (Mc Murdo Dry Valleys). A tight correlation was observed between the desiccation and radiation tolerance of the investigated desert strains and the absence of oxidative damage to proteins. The efficiency of the antioxidant systems of the desert strains of Chroococcidiopsis was highlighted also by the lack of protein carbonylation until treatment with 1M of oxygen peroxide. The phylogenetic analysis of the investigated 11 desert strains of Chroococcidiopsis is reported. References Baque, M. et al. 2013a. Biofilm and planktonic lifestyles differently support the resistance of the desert cyanobacterium Chroococcidiopsis under space and Martian simulations. Origin of Life and Evolution of Biospheres 3,377-89. Baque, M. et al. 2013b. Endurance of the endolithic desert cyanobacterium Chroococcidiopsis under UVC radiation. Extremophiles 17,161-169. Billi, D. et 2011. Damage escape and repair in dried Chroococcidiopsis spp. from hot and cold deserts exposed to simulated space and Martian conditions. Astrobiology 11,65-73. Daly, M.J. et al., 2007. Protein oxidation implicated as the primary determinant of bacterial radioresistance. PLoS Biology, 5(4), p.e92. Fredrickson, J.K. et al. (2008) Protein oxidation: key to bacterial desiccation resistance? Int J Syst Evol Microbiol 2:393-403 Friedmann, E.I. 1980. Endolithic microbial life in hot and cold deserts. Origins of Life and Evolution of Biospheres10, 223-235. Verseux, C. et al. 2017. Evaluation of the resistance of Chroococcidiopsis spp. to sparsely and densely ionizing irradiation. Astrobiology 17,118-125 This work was supported by the Italian National Antarctic Research Program This work is dedicated to the memory of Roseli Ocampo-Friedmann and E. Imre Friedmann who pioneered the research on Chroococcidiopsis and life in extreme environments
Cyprien Verseux - One of the best experts on this subject based on the ideXlab platform.
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Dried Biofilms of Desert Strains of Chroococcidiopsis Survived Prolonged Exposure to Space and Mars-like Conditions in Low Earth Orbit.
Astrobiology, 2019Co-Authors: Daniela Billi, Mickael Baqué, Cyprien Verseux, Claudia Mosca, Claudia Fagliarone, Elke Rabbow, Clelia Staibano, Petra RettbergAbstract:Abstract Dried biofilms and dried multilayered planktonic counterparts obtained from three desert strains of Chroococcidiopsis were exposed to low Earth conditions by using the EXPOSE-R2 facility o...
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A Desert Cyanobacterium under Simulated Mars-like Conditions in Low Earth Orbit: Implications for the Habitability of Mars
Astrobiology, 2019Co-Authors: Daniela Billi, Mickael Baqué, Cyprien Verseux, Claudia Fagliarone, Alessandro Napoli, Jean-pierre De VeraAbstract:Abstract In the ESA space experiment BIOMEX (BIOlogy and Mars EXperiment), dried Chroococcidiopsis cells were exposed to Mars-like conditions during the EXPOSE-R2 mission on the International Space...
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Avoidance of protein oxidation correlates with the desiccation and radiation resistance of hot and cold desert strains of the cyanobacterium Chroococcidiopsis
Extremophiles, 2017Co-Authors: Claudia Fagliarone, Mickael Baqué, Cyprien Verseux, Claudia Mosca, Annick Wilmotte, Ilaria Ubaldi, Daniela BilliAbstract:To investigate the relationship between desiccation and the extent of protein oxidation in desert strains of Chroococcidiopsis a selection of 10 isolates from hot and cold deserts and the terrestrial cyanobacterium Chroococcidiopsis thermalis sp. PCC 7203 were exposed to desiccation (air-drying) and analyzed for survival. Strain CCMEE 029 from the Negev desert and the aquatic cyanobacterium Synechocystis sp. PCC 6803 were further investigated for protein oxidation after desiccation (drying over silica gel), treatment with H_2O_2 up to 1 M and exposure to γ-rays up to 25 kGy. Then a selection of desert strains of Chroococcidiopsis with different survival rates after prolonged desiccation, as well as Synechocystis sp. PCC 6803 and Chroococcidiopsis thermalis sp. PCC 7203, were analyzed for protein oxidation after treatment with 10 and 100 mM of H_2O_2. Results suggest that in the investigated strains a tight correlation occurs between desiccation and radiation tolerance and avoidance of protein oxidation.
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Unravelling the secret of the resistance of desert strains of Chroococcidiopsis to desiccation and radiation
2017Co-Authors: Daniela Billi, Mickael Baqué, Fagliarone, Cyprien Verseux, Claudia Mosca, Annick WilmotteAbstract:Chroococcidiopsis is a unicellular cyanobacterial genus that is growing in extreme dry conditions, either in low or high temperatures. At the lower end of the spectrum, they live as cryptoendoliths in rocks of the Mc Murdo Dry Valleys in Antarctica where they were discovered by Imre Friedmann, while at the higher end, they grow as hypoliths/endoliths in hot deserts, e.g. Negev, Gobi, Atacama (Friedman, 1980). The capacity of desert strains of Chroococcidiopsis to stabilize their sub-cellular organization is so efficient that, when dried, they can cope with simulated space and Martian conditions (Billi et al 2011 ; Baque et al. 2013a) as well as with high doses of ionizing and UV radiations (Verseux et al. 2017 ; Baque et al. 2013b). Since it is known for radiation/desiccation tolerant bacteria that the capability to avoid protein oxidation is critical to cope with such stressors (Frederickson et al. 2008; Daly et al. 2007), the present study investigates the protein oxidation after prolonged desiccation, irradiation with gamma-rays up to 25kGy and treatment with hydrogen peroxide in a selection of desert Chroococcidiopsis isolates, including 2 Antarctic strains: CCMEE134 and CMEE171 isolated from Beacon Valley and University Valley, respectively (Mc Murdo Dry Valleys). A tight correlation was observed between the desiccation and radiation tolerance of the investigated desert strains and the absence of oxidative damage to proteins. The efficiency of the antioxidant systems of the desert strains of Chroococcidiopsis was highlighted also by the lack of protein carbonylation until treatment with 1M of oxygen peroxide. The phylogenetic analysis of the investigated 11 desert strains of Chroococcidiopsis is reported. References Baque, M. et al. 2013a. Biofilm and planktonic lifestyles differently support the resistance of the desert cyanobacterium Chroococcidiopsis under space and Martian simulations. Origin of Life and Evolution of Biospheres 3,377-89. Baque, M. et al. 2013b. Endurance of the endolithic desert cyanobacterium Chroococcidiopsis under UVC radiation. Extremophiles 17,161-169. Billi, D. et 2011. Damage escape and repair in dried Chroococcidiopsis spp. from hot and cold deserts exposed to simulated space and Martian conditions. Astrobiology 11,65-73. Daly, M.J. et al., 2007. Protein oxidation implicated as the primary determinant of bacterial radioresistance. PLoS Biology, 5(4), p.e92. Fredrickson, J.K. et al. (2008) Protein oxidation: key to bacterial desiccation resistance? Int J Syst Evol Microbiol 2:393-403 Friedmann, E.I. 1980. Endolithic microbial life in hot and cold deserts. Origins of Life and Evolution of Biospheres10, 223-235. Verseux, C. et al. 2017. Evaluation of the resistance of Chroococcidiopsis spp. to sparsely and densely ionizing irradiation. Astrobiology 17,118-125 This work was supported by the Italian National Antarctic Research Program This work is dedicated to the memory of Roseli Ocampo-Friedmann and E. Imre Friedmann who pioneered the research on Chroococcidiopsis and life in extreme environments
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Evaluation of the Resistance of Chroococcidiopsis spp. to Sparsely and Densely Ionizing Irradiation
Astrobiology, 2017Co-Authors: Cyprien Verseux, Mickael Baqué, Claudia Fagliarone, Riccardo Cifariello, Marina Raguse, Ralf Moeller, Daniela BilliAbstract: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.
Jean-pierre De Vera - One of the best experts on this subject based on the ideXlab platform.
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Biomarker Preservation and Survivability Under Extreme Dryness and Mars-Like UV Flux of a Desert Cyanobacterium Capable of Trehalose and Sucrose Accumulation
Frontiers in Astronomy and Space Sciences, 2020Co-Authors: Claudia Fagliarone, Mickael Baqué, Jean-pierre De Vera, Alessandro Napoli, Salvatore Chiavarini, Daniela BilliAbstract:Unravelling how long life can persist under extreme dryness and what kind of environmental extremes can be faced by dried microorganisms, is relevant to understand Mars habitability and to search for life on planets with transient liquid water availability. Since trehalose and sucrose stabilize dried anhydrobiotes, an in silico survey of the genome of the desert cyanobacterium Chroococcidiopsis sp. CCMEE 029 was performed to identify pathways for trehalose and sucrose biosynthesis. The expression of the identified genes was induced in response to desiccation and trehalose and sucrose accumulation was detected in dried cells. This adaptation strategy enabled viability and biomarker permanence under extreme dryness and Mars-like UV flux. Chroococcidiopsis survivors were scored in 7-year dried biofilms mixed with phyllosilicatic Mars regolith simulant and exposed to 5.5 x 103 kJ/m2 of a Mars-like UV flux. No survivors occurred after exposure to 5.5 x 105 kJ/m2, although in dead cells, photosynthetic pigments and nucleic acids, both DNA and RNA, were still detectable. This suggested that dried biofilms mixed with phyllosilicatic Martian regolith simulant are suitable candidates to identify biosignatures embedded in planetary analogue minerals as planned in the future BioSigN (BioSignatures and habitable Niches) space mission to be performed outside the International Space Station.
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A Desert Cyanobacterium under Simulated Mars-like Conditions in Low Earth Orbit: Implications for the Habitability of Mars
Astrobiology, 2019Co-Authors: Daniela Billi, Mickael Baqué, Cyprien Verseux, Claudia Fagliarone, Alessandro Napoli, Jean-pierre De VeraAbstract:Abstract In the ESA space experiment BIOMEX (BIOlogy and Mars EXperiment), dried Chroococcidiopsis cells were exposed to Mars-like conditions during the EXPOSE-R2 mission on the International Space...
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The BOSS and BIOMEX space experiments on the EXPOSE-R2 mission: endurance of the desert cyanobacterium Chroococcidiopsis under simulated space vacuum, Martian atmosphere, UVC radiation and temperature extremes.
Acta Astronautica, 2013Co-Authors: Mickael Baqué, Jean-pierre De Vera, Petra Rettberg, Daniela BilliAbstract:The proposed space experiments BOSS (Biofilm Organisms Surfing Space) and BIOMEX (BIOlogy and Mars experiment) will take place on the space exposure facility EXPOSE-R2 on the International Space Station (ISS), which is set to be launched in 2014. In BOSS the hypothesis to be tested is that microorganisms grown as biofilms, hence embedded in self-produced extracellular polymeric substances, are more tolerant to space and Martian conditions compared to their planktonic counterparts. Various microbial biofilms have been developed including those obtained from the cyanobacterium Chroococcidiopsis isolated from hot and cold deserts. The prime objective of BIOMEX is to evaluate to what extent biomolecules are resistant to, and can maintain their stability under, space and Mars-like conditions; therefore a variety of pigments and cell components are under investigation to establish a biosignature data base; e.g. a Raman spectral library to be used for extraterrestrial life biosignatures. The secondary objective of BIOMEX is to investigate the endurance of extremophiles, focusing on their interactions with Lunar and Martian mineral analogues. Ground-based studies are currently being carried out in the framework of EVTs (Experiment Verification Tests) by exposing selected organisms to space and Martian simulations. Results on a desert strain of Chroococcidiopsis obtained from the first set of EVT, e.g. space vacuum, Mars atmosphere, UVC radiation, temperature cycles and extremes, suggested that dried biofilms exhibited an enhanced survival compared to planktonic lifestyle. Moreover the protection provided by a Martian mineral analogue (S-MRS) to the sub-cellular integrities of Chroococcidiopsis against UVC radiation supports the endurance of this cyanobacterium under extraterrestrial conditions and its relevance in the development of life detection strategies.
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Microbial rock inhabitants survive hypervelocity impacts on Mars-like host planets: First phase of lithopanspermia experimentally tested
Astrobiology, 2008Co-Authors: Gerda Horneck, Charles S Cockell, Ralf Moeller, Dieter Stöffler, Sieglinde Ott, Ulrich Hornemann, C. Meyer, Jean-pierre De Vera, Jörg Fritz, Sara SchadeAbstract:ABSTRACT The scenario of lithopanspermia describes the viable transport of microorganisms via meteorites. To test the first step of lithopanspermia, i.e., the impact ejection from a planet, systematic shock recovery experiments within a pressure range observed in martian meteorites (5–50 GPa) were performed with dry layers of microorganisms (spores of Bacillus subtilis, cells of the endolithic cyanobacterium Chroococcidiopsis, and thalli and ascocarps of the lichen Xanthoria elegans) sandwiched between gabbro discs (martian analogue rock). Actual shock pressures were determined by refractive index measurements and Raman spectroscopy, and shock temperature profiles were calculated. Pressure-effect curves were constructed for survival of B. subtilis spores and Chroococcidiopsis cells from the number of colony-forming units, and for vitality of the photobiont and mycobiont of Xanthoria elegans from confocal laser scanning microscopy after live/dead staining (FUN-I). A vital launch window for the transport of...
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Experimental evidence for the potential impact ejection of viable microorganisms from Mars and Mars-like planets
Icarus, 2007Co-Authors: Dieter Stöffler, Charles S Cockell, Gerda Horneck, Ralf Moeller, Sieglinde Ott, Ulrich Hornemann, C. Meyer, Jean-pierre De Vera, Jörg Fritz, Natalia ArtemievaAbstract:Bacterial spores (Bacillus subtilis), cyanobacteria (Chroococcidiopsis sp.), and lichen (Xanthoria elegans) embedded in martian analogue rock (gabbro) were exposed to shock pressures between 5 and 50 GPa which is the range of pressures observed in martian meteorites. The survival of Bacillus subtilis and Xanthoria elegans up to 45 GPa and of Chroococcidiopsis sp. up to 10 GPa supports the possibility of transfer of life inside meteoroids between Mars and Earth and it implies the potential for the transfer of life from any Mars-like planet to other habitable planets in the same stellar system.