Radiation-driven Prebiotic Chemistry and Biosignatures Detection

IntroductionEarth's prebiotic chemistry is based on water and thermal sources (internal or external to the Earth)1,2. In contrast, the prebiotic chemistry of extraterrestrial systems (Mars, Europa, Titan, Enceladus, etc.) is primarily driven by radiation sources3–5. Recent work leveraging Martian and ocean world natural and synthetic analog materials was used to classify biotic and abiotic organics in the context of multiple planetary missions (with Curiosity, Perseverance, Rosalind Franklin, and Dragonfly)6–9. Our experiments yielded a chemical network that abiotically produced building blocks of life (e.g., amino acids up to small-peptides and thiamine and nucleobases up to nucleotides) when synthetic analogs were hydrolyzed in contact with salts and/or exposed to X-/Ɣ-rays and proton irradiation7,10. The different irradiation simulations on natural and synthetic analog materials analyzed by spaceflight instruments and/or high-resolution mass spectrometry assessed the question: How fast may the transition from prebiotic abiotic chemistry to biotic chemistry take place? A “primitive biochemistry transition” would occur and contradicts the expectation of a clear biotic-abiotic boundary between the production of polymers abiotically and biologically in a primitive environment. Indeed, our experiments and some meteoritic data revealed the production of small biopolymers abiotically from a few hundred to tens of thousands of years10–12.Materials and MethodsTo address the influence of different radiation sources on organic matter transformation as a pure standard or in a matrix/medium analog to extraterrestrial surfaces, we got access to multiple radiation facilities (SOLEIL-France and CLS-Canada synchrotron for X-rays, GSFC-NASA-USA for Ɣ-ray and protons radiations) and analyzed with X-ray, infrared spectroscopy and GC-MS/orbitrap.To simulate Mars near surface environment, we first studied soft/mid X-rays that could be indirectly produced by the main elements in the Martian regolith (secondary X-rays by carbon (0.28 keV), silica (1.74 keV), sulfur (2.31 keV), chlorine (2.62 keV), or iron (6.40 keV)). Those experiments focused on amino acids (L-Ala, L or D/L-Phe), peptides (Ala-Gly), carboxylic acids (trimesic, lignoceric, and benzoic acids), nucleobases (adenine and uracil), and organics detected by the Sample Analysis at Mars (SAM) at Gale crater (chlorobenzene and thiophene).We then simulated the radiative conditions at higher energies for Mars and ocean worlds (using γ-rays at 1-300 krad equivalent to 6 months-1000 Titan years’ simulation, for instance, and protons at 200 MeV – e.g., a few Titan months) and chemical environment that tropospheric aerosols or surface deposits may undergo on Titan to forecast Dragonfly operations, analysis, and interpretations. ResultsLow radiation energies enhance the production of building blocks of life (e.g., nucleobases, amino acids, sugars) (Fig. 1).Low eradiation energies induce interactions between organic matter and inorganic soluble or solid material (bond and/or form organo-mineral/salt products).While low energy radiation enhanced the production of building blocks of life (BBLs), high energy radiation degraded faster the prebiotic precursors than produced the BBLs (Fig. 2). High radiation energies (photons and particles) benefit to the polymerization.ConclusionsWithin protected environments (e.g., Mars subsurface environments – below 10 cm – from SAM-MSL data and investigation for MOMA-ExoMars), biosignatures may be preserved for at least 100 million years thanks to salts.A “primitive biochemistry transition” may have occurred in crater impacts few billion years ago (e.g., at Gale and Jezero craters) and contradicts the expectation of a clear biotic-abiotic boundary between the production of polymers abiotically and biologically in a primitive environment. Indeed, our experiments and some meteoritic data revealed the abiotic production of small biopolymers from a few hundred to tens of thousands of years driven by radiation and a catalytic substrate.ReferencesWestall, F. et al. A Hydrothermal-Sedimentary Context for the Origin of Life. Astrobiology 18, 259–293 (2018). Westall, F., Brack, A., Fairén, A. G. & Schulte, M. D. Setting the geological scene for the origin of life and continuing open questions about its emergence. Frontiers in Astronomy and Space Sciences 9, (2023). Cooper, J. F., Johnson, R. E., Mauk, B. H., Garrett, H. B. & Gehrels, N. Energetic Ion and Electron Irradiation of the Icy Galilean Satellites. Icarus 149, 133–159 (2001). Cockell, C. S. & Andrady, A. L. The Martian and extraterrestrial UV radiation environment--1. Biological and closed-loop ecosystem considerations. Acta Astronaut 44, 53–62 (1999). Dartnell, L. R., Desorgher, L., Ward, J. M. & Coates, A. J. Modelling the surface and subsurface Martian radiation environment: Implications for astrobiology. Geophysical Research Letters 34, (2007). Boulesteix, D. et al. Geochemical and Metabolomic study of few Yellowstone spring systems over a range of pH. in Life in the Sub Surface: Habitats, Species, Metabolism and Survival Strategies (Angra do Heroismo, Portugal, 2023). Buch, A. et al. Influence of the secondary X-Rays on the organic matter at Mars’ near-surface. in AGU Fall Meeting 2022 P12A-08 (Chicago, United States, 2022). Boulesteix, D. et al. Extremophile Metabolite Study to Detect Potential Biosignatures and Interpret Future Gas Chromatography-Mass spectrometry Ocean Worlds in situ analysis (e.g. Dragonfly mission with its DraMS instrument and EuropaLander with its EMILI instrument). in AGU Fall Meeting Abstracts vol. 2022 P55G-1650 (2022). Millan, M. et al. Sedimentary Organics in Glen Torridon, Gale Crater, Mars: Results From the SAM Instrument Suite and Supporting Laboratory Analyses. Journal of Geophysical Research: Planets 127, e2021JE007107 (2022). Boulesteix, D. et al. Titan Simulation for DraMS Analysis and Prebiotic Chemistry Interpretation Using Analog Materials Exposed to Gamma-rays and Protons. AGU24 (2024). Schmitt-Kopplin, P. et al. High molecular diversity of extraterrestrial organic matter in Murchison meteorite revealed 40 years after its fall. Proceedings of the National Academy of Sciences 107, 2763–2768 (2010). Barks, H. L. et al. Guanine, adenine, and hypoxanthine production in UV-irradiated formamide solutions: relaxation of the requirements for prebiotic purine nucleobase formation. ChemBioChem 11, 1240–1243 (2010).

Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.