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Powder X-Ray diffraction patterns of hematite (Fe 2 O 3 ). The figures indicate the d-spacing of the several peaks in angstroms. The intensity increase at ∼10 °2 θ is produced by the X-ray fluorescence of Fe.

Powder X-Ray diffraction patterns of hematite (Fe 2 O 3 ). The figures indicate the d-spacing of the several peaks in angstroms. The intensity increase at ∼10 °2 θ is produced by the X-ray fluorescence of Fe.

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The detection of organic molecules associated with life on Mars is one of the main goals of future life-searching missions such as the ESA-Roscosmos ExoMars and NASA 2020 mission. In this work we studied the preservation of 25 amino acids that were spiked onto the Mars-relevant minerals augite, enstatite, goethite, gypsum, hematite, jarosite, labra...

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... mineral phases in the estimated order of abundance: volcanic glass, pyroxene, olivine, and labradorite. Jarosite is of the natrojarosite variety. Olivine is forsterite. The augite and enstatite contain some traces of amphibole; the non- tronite and montmorillonite contain traces of quartz; the other minerals are pure at the XRD detection level. Fig. 1 shows the X-ray pattern of hematite as an ...
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... addition, we would expect that the amino acids more resistant to UV radiation and less prone to decarboxylation would be α-aminoisobutyric and isovaline, which are doubly substituted in the α-carbon. A group of our results agree with the overall effect of substitution in the α-carbon described above ( Tables 1-3 ). For instance, glycine was less preserved than α-aminoisobutyric and isovaline in all augite, basaltic lava, enstatite and jarosite experiments 2, 3 and 4 ( Tables 1-3 ). ...
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... group of our results agree with the overall effect of substitution in the α-carbon described above ( Tables 1-3 ). For instance, glycine was less preserved than α-aminoisobutyric and isovaline in all augite, basaltic lava, enstatite and jarosite experiments 2, 3 and 4 ( Tables 1-3 ). However, it is evident that the alkyl substituent groups are not the only factor contributing towards the stability of the amino acids. ...
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... factors probably also play a role in the stabilization of amino acids against UV light, but their complexity is beyond the scope of this article. We observed that D and L amino acids were equally degraded in the simulations ( Tables 1-3 ). This lack of enantiomeric pref- erence regarding UV-induced degradation is consistent with the observations of Orzechowska et al. (2007) for D,L-aspartic acid, D,L-glutamic acid and D,L-phenylalanine. ...

Citations

... Lacustrine carbonates in Jezero Crater also offer high preservation potential (Horgan et al., 2020). A study of amino acid preservation in simulated martian conditions found the highest preservation in smectites and sulfates (dos Santos et al., 2016). ...
Article
An origin of Earth life on Mars would resolve significant inconsistencies between the inferred history of life and Earth's geologic history. Life as we know it utilizes amino acids, nucleic acids, and lipids for the metabolic, informational, and compartment-forming subsystems of a cell. Such building blocks may have formed simultaneously from cyanosulfidic chemical precursors in a planetary surface scenario involving ultraviolet light, wet-dry cycling, and volcanism. On the inferred water world of early Earth, such an origin would have been limited to volcanic island hotspots. A cyanosulfidic origin of life could have taken place on Mars via photoredox chemistry, facilitated by orders-of-magnitude more sub-aerial crust than early Earth, and an earlier transition to oxidative conditions that could have been involved in final fixation of the genetic code. Meteoritic bombardment may have generated transient habitable environments and ejected and transferred life to Earth. Ongoing and future missions to Mars offer an unprecedented opportunity to confirm or refute evidence consistent with a cyanosulfidic origin of life on Mars, search for evidence of ancient life, and constrain the evolution of Mars' oxidation state over time. We should seek to prove or refute a martian origin for life on Earth alongside other possibilities.
... The idea that the building blocks of life (dos Santos et al., 2016;Laurent et al., 2019) or even dried cells may be preserved (Bryce et al., 2015;Baqué et al., 2016) can be expanded to currently dry planets like Mars (Baqué et al., 2020). For example, one of our samples-Bacillus safensis-has also been isolated from the spacecraft Mars Odyssey orbiter (Satomi et al., 2006) and could have survived the extreme radiation environment in space. ...
Article
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With thousands of discovered planets orbiting other stars and new missions that will explore our solar system, the search for life in the universe has entered a new era. However, a reference database to enable our search for life on the surface of icy exoplanets and exomoons by using records from Earth's icy biota is missing. Therefore, we developed a spectra catalogue of life in ice to facilitate the search for extraterrestrial signs of life. We measured the reflection spectra of 80 microorganisms-with a wide range of pigments-isolated from ice and water. We show that carotenoid signatures are wide-ranged and intriguing signs of life. Our measurements allow for the identification of such surface life on icy extraterrestrial environments in preparation for observations with the upcoming ground-and space-based telescopes. Dried samples reveal even higher reflectance, which suggests that signatures of surface biota could be more intense on exoplanets and moons that are drier than Earth or on environments like Titan where potential life-forms may use a different solvent. Our spectra library covers the visible to near-infrared and is available online. It provides a guide for the search for surface life on icy worlds based on biota from Earth's icy environments.
... For example, biofilms prepared from the intercalation of amino acids and montmorillonite had characteristics and biocompatibility in tissue engineering [95]. As amino acids are the fundamental structures that proteins construct, understanding the interactions and stabilization of different amino acids and the structures of clay minerals can lead to critical applications of these compounds related to the immune system, enzymatic catalysis, and biochemical evolution of life on earth [96][97][98][99]. ...
Article
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Clay minerals are often used due to their high adsorption capacity, which has sparked interest in their biological applications to stabilize drugs and pharmaceutical products. This research aims to summarize information about the stability of drugs, cosmetics, dermocosmetics, and pharmaceutical compounds incorporated in the structure of different clay minerals. The databases used to search the articles were Web of Science, Scopus, PubMed, and Science Direct. Photostabilization of these compounds is reviewed and its importance demonstrated. For biological applications, the increase in solubility and bioavailability of clay minerals has proven useful for them as drug carriers. While their natural abundance, low toxicity, and accessible cost have contributed to classical applications of clay minerals, a wide range of interesting new applications may be facilitated, mainly through incorporating different organic molecules. The search for new functional materials is promising to challenge research on clay minerals in biological or biotechnological approaches.
... In addition, the mineralogy of the Martian regolith has an influence on the preservation of amino acids. Clay minerals or sulfate rich environments have been reported to show higher preservation rates compared to minerals containing ferrous iron (dos Santos et al., 2016). This effect was also noted in space exposure experiments where amino acids intermixed with meteorite powder had a higher stability than without (Bertrand et al., 2015). ...
Article
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The identification of reliable biomarkers, such as amino acids, is key for the search of extraterrestrial life. A large number of microorganisms metabolize, synthesize, take up and excrete amino acids as part of the amino acid metabolism during aerobic and/or anaerobic respiration or in fermentation. In this work, we investigated whether the anaerobic microbial metabolism of amino acids could leave a secondary biosignature indicating biological activity in the environment around the cells. The observed fingerprints would reflect the physiological capabilities of the specific microbial community under investigation. The metabolic processing of an amino acid mixture by two distinct anaerobic microbial communities collected from Islinger Mühlbach (ISM) and Sippenauer Moor (SM), Germany was examined. The amino acid mixture contained L-alanine, β-alanine, L-aspartic acid, DL-proline, L-leucine, L-valine, glycine, L-phenylalanine and L-isoleucine. In parallel, an amino acid spiked medium without microorganisms was used as a control to determine abiotic changes over time. Liquid chromatography mass spectrometry (LC-MS) was used to track amino acid changes over time. When comparing to the control samples that did not show significant changes of amino acids concentrations over time, we found that glycine was almost completely depleted from both microbial samples to less than 3% after the first two weeks- This results indicates a preferential use of this simple amino acid by these microbial communities. Although glycine degradation can be caused by abiotic processes, these results show that its preferential depletion in an environment would be consistent with the presence of life. We found changes in most other amino acids that varied between amino acids and communities, suggesting complex dynamics with no clear universal pattern that might be used as a signature of life. However, marked increases in amino acids, caused by cellular synthesis and release into the extracellular environment (e.g., alanine), were observed and could be considered a signature of metabolic activity. We conclude, that substantial anomalous enhancements of some amino acids against the expected abiotic background concentration may be an agnostic signature of the presence of biological processes.
... Salar soils contain biomarkers in Neogene evaporites that record past aqueous conditions (Pueyo et al., 2002). Lipid biomarkers, which are diagnostic of prokaryotic life (Wilhelm et al., 2017(Wilhelm et al., , 2019Sánchez-García et al., (2018)), are wellpreserved in salars due to the hyperaridity (Wilhelm et al., 2017) and presence of halite and gypsum salts (Fernández-Remolar et al., 2013;dos Santos et al., 2016). ...
... All six classes of lipid biomarkers have been detected in clay minerals at BON, though the age of these biomarkers has not been determined (Doran et al., 1994). Lipid biomarkers are also well-preserved in halide minerals, such as the halite and gypsum salts found in ATC (Fernández-Remolar et al., 2013;dos Santos et al., 2016). At RIO, 2-8 Ma fossils are well-preserved, likely due to the presence of iron oxide (microfossils) and goethite (macrofossils) (Fernández-Remolar and Knoll, 2008). ...
Article
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Past environments on Mars contained abundant water, suggesting certain regions may have been conducive to life as we know it and implying the potential for microbial inhabitants. Gale and Jezero craters, home of the Perseverance and Curiosity rovers, hosted ancient lakes that experienced periods of active hydrologic cycling and prolonged drying intervals. Exploration of these basins (and future operations on Mars) will benefit from detailed characterizations of analogous environments on Earth, where life detection strategies at various spatial scales (i.e., rover to orbiter) can be tested and validated. Investigations of terrestrial analogs are critical for understanding (1) how microorganisms generate chemical biosignatures in environments characterized by multiple extreme conditions; (2) the impact of environmental conditions and mineralogy on biosignature preservation; and (3) what technologies and techniques are needed to detect biosignatures remotely or in situ. Here, we survey five terrestrial sites analogous to climate conditions proposed for Late Noachian to Early Hesperian Mars, when craters are thought to have hosted active lakes. We review the geologic setting, environmental conditions, microbial habitability, extant microbial communities, and preserved biomarkers at each analog and discuss their relevance to the search for signs of life in Martian craters with in situ and remote instrumentation. The analogs range from active to desiccated lake systems, temperate to hyper-arid climates, and have acidic to neutral-pH and hypo- to hyper-saline waters. Each analog hosts microorganisms adapted to multiple extremes (polyextremophiles), including aspects of water availability (i.e., surface waters versus shallow subsurface water versus groundwater) and physiochemistry (e.g., water activity, salinity, temperature, alkalinity, pH, and redox potential) that can form macrobiological features such as microbial mats. Comparing the expected achievable spatial resolution of several key Mars instruments to the spatial extent of macrobiological features at each analog reveals that most features are unlikely to be resolved from orbit and require rover-scale instruments for detection. We recommend that future studies at these analogs use multi-scale remote sensing surveys to determine thresholds for detecting macrobiological features and map how patterns in mineralogy or physical characteristics of environments correlate to modern-day microbial communities or preserved biomarkers. It will also be critical to determine how the characteristics of macrobiological features, such as areal extent, percent cover, thickness, pigments, etc., impact detectability thresholds. These findings can provide vital information on potential topographic or spectroscopic signatures of life, and at what scales they are detectable. This research is critical to guide sample collection locations within craters like Jezero, and for selecting landing sites for future missions in evaporative Martian basins and other rocky bodies.
... A cursory visual inspection of the WLS's XRD profile confirms the presence of titanium oxide (TiO 2 ) [83], hematite (Fe 2 O 3 ) [84], muscovite-2M1 (KAl 2 (Si 3 Al)O 10 (OH) 2 ) [85], and silica (SiO 2 )/silica dimethyl silylate (C 2 H 6 Cl 2 O 2 Si 2 ) [86]. The titanium dioxide (TiO 2 , CI 77891), a bright and opaque pigment, acting as a natural sunscreen/sunblock, is adopted to add color to the lips [87]. ...
Article
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This investigation is dedicated to unlocking the hidden potential of discarded cosmetics towards building green sustainable road pavements in the future. It is particularly aiming at exploring waste lipstick (WLS) as a high-quality functional additive for advanced asphalt mix technologies. To fuel this novel innovation, the effect of various WLS doses (e.g., 5, 10, and 15 wt.%) on the performance of base AP-5 asphalt cement was studied in detail. A wide array of cutting-edge analytical lab techniques was employed to inspect in-depth the physicochemical, microstructural, thermo-morphological, and rheological properties of resultant admixtures including: elemental analysis, Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thin-layer chromatography-flame ionization detection (TLC-FID), scanning electron microscopy (SEM), atomic force microscopy (AFM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), needle penetration, ring and ball softening point, Brookfield viscometer, ductility, and dynamic shear rheometer (DSR) tests. Unlike the unstable response of asphaltenes, the additive/artificial aging treatments increased the fraction of resins the most, and decreased that of aromatics; however, asphaltenes did not impair the saturates portion, according to Iatroscan research. FT-IR scan divulged that the WLS-asphalt interaction was physical rather than chemical. XRD diagnosis not only revealed an obvious correlation between the asphaltenes content and the fresh-binder crystallinity but also revealed the presence of fillers in the WLS, which may generate outstanding technical qualities to bituminous mixes. According to AFM/SEM analyses, the stepwise incorporation of WLS grew the magnitude of the “bee-shaped” microstructures and extended the roughness rate of unaged/aged binders. The prolonged consumption of the high thermal-stable additive caused a remarkable drop in the onset degradation and glass transition temperature of mixtures, thus enhancing their workability and low-temperature performance, according to TGA/DTGA/DSC data. The DSR and empirical rheological experiments demonstrated that the WLS could effectively lower the manufacturing and compaction temperatures of asphalt mixes and impart them with valuable anti-aging/fatigue-cracking assets. In a nutshell, the use of waste lipstick as an asphalt modifier is viable and cost-effective and could attenuate the pollution arisen from the beauty sector, while improving the performance of hot/warm asphalt mixes (HAM/WAM) and extending the service life of roadways.
... Minerals can also concentrate organic molecules and they have also proved to act as protective shields for organic molecules under harsh environmental conditions [151,152]. These interesting properties of minerals led to the hypothesis that minerals are involved in the preservation of organic content and in the generation of more complex species. ...
... Often seen as the result of billion years of evolution of the environment on Earth and sometimes even of life's evolution, several studies propose that minerals, especially clays, might have played a crucial role in the emergence of life. In addition to their catalytic properties [144][145][146], they might have selected, preconcentrated and protected specific molecules including amino acids, the monomeric building blocks of proteins, from harsh environmental conditions [151,152,[155][156][157]. During the polymerization processes of nucleotides, they can moreover increase regioselectivity [184], and stereoselectivity at each monomer addition [188][189][190]. ...
Thesis
What caused the emergence of life? Which physico-chemical processes are involved in the selection and organization of the specific molecules that gave birth to the first cells able to take over the primary metabolic tasks like growth and reproduction? Mankind have been fascinated for centuries by these questions and have provided a plethora of scientific or religious theories and hypotheses. Yet, they remain unanswered due to their complexity. The Earth is full of very diverse and complex forms of life but sharing a fundamental and unique property of nature that cannot be ignored when deciphering the origins of life: the homochirality. Essential biological macromolecules such as DNA, RNA, proteins, and phospholipids are made of small chiral units of the same handedness; a curiosity since enantioselective synthesis is not usual without biological input. The origin of this biomolecular asymmetry is still unknown, but it is probably one of the first steps to discover the origins of life. The scientific community proposes the path to homochirality in two stages which are the symmetry breaking or the generation of small enantiomeric excesses, followed by their amplification. This manuscript is essentially focused on the first step.Two processes capable of such symmetry breaking will be discussed here: the interaction of circularly polarized light with organic matter and the interaction between organic matter and mineral matrices. The first chapter summarizes the state of the art on both topics. The second chapter introduces our analytical approach and describes the development of new methods to perform enantioselective analyses of complex mixtures targeting sugars in complex mixtures, a crucial family of chemical compounds for all living systems, by gas chromatography coupled to time-of-flight mass spectrometry. Several methods were tested and compared according to different parameters including sensitivity, enantiomeric resolution, stability, and enantiomeric excess measurements. The third chapter investigates minerals and their capacity to induce a small imbalance between the enantiomers of amino acids, including proteinogenic amino acids. Martian minerals were studied in terms of their adsorption potential as well as the effect of enantioselective adsorption by chiral quartz on the amino acids alanine and leucine. Both axes result in interesting induced enantiomeric excesses and open new perspectives in the field. In the last chapter, we explored the optical activity of key molecules in the gas phase. For this purpose, a temperature- and pressure-controlled gas cell coupled was specifically built. The circular dichroism and anisotropy spectra of seven amino acids and propylene oxide – the first chiral molecule observed in the interstellar medium – were recorded in the gas phase, where any asymmetry is solely determined by the genuine electromagnetic transition moments. The data, complemented by quantum chemical calculation, provide new insights into the original gas phase asymmetric photochemical reactions in interstellar environments for the enantiomeric selection of life’s L-amino acids.
... Brines can destabilize clay minerals and destroy intimate associations with organic molecules, potentially reducing the preservation capacity of the rock record. However, subsequent readsorption on sulfates may be an efficient check on organic decay (50). Although brine-driven destruction of clay minerals complicates geological interpretation, water released during this process would have acted as a negative feedback, slowing the pace of planetary desiccation and potentially extending the period in which Mars had surface liquid water. ...
Article
Full-text available
Mars’ sedimentary rock record preserves information on geological (and potential astrobiological) processes that occurred on the planet billions of years ago. The Curiosity rover is exploring the lower reaches of Mount Sharp, in Gale crater on Mars. A traverse from Vera Rubin ridge to Glen Torridon has allowed Curiosity to examine a lateral transect of rock strata laid down in a martian lake ~3.5 billion years ago. We report spatial differences in the mineralogy of time-equivalent sedimentary rocks <400 meters apart. These differences indicate localized infiltration of silica-poor brines, generated during deposition of overlying magnesium sulfate–bearing strata. We propose that destabilization of silicate minerals driven by silica-poor brines (rarely observed on Earth) was widespread on ancient Mars, because sulfate deposits are globally distributed.
... It should be noted that organic matter may be intimately linked to phyllosilicates at the surface, due to their formation evolution together in aqueous environments, which could have preserved some organic matter [52,53]. The organic-mineral association can delay the degradation of aliphatic compounds for some time [54,55], but further experiments in conditions specific to Ceres are required. Mechanisms leading to the concentration of organic matter in the shallow subsurface and regolith of Ceres remain to be investigated. ...
Article
Full-text available
Organic matter directly observed at the surface of an inner planetary body is quite infrequent due to the usual low abundance of such matter and the limitation of the infrared technique. Fortuitously, the Dawn mission has revealed, thanks to the Visible and InfraRed mapping spectrometer (VIR), large areas rich in organic matter at the surface of Ceres, near Ernutet crater. The origin of the organic matter and its abundance in association with minerals, as indicated by the low altitude VIR data, remains unclear, but multiple lines of evidence support an endogenous origin. Here, we report an experimental investigation to determine the abundance of the aliphatic carbon signature observed on Ceres. We produced relevant analogues containing ammoniated-phyllosilicates, carbonates, aliphatic carbons (coals), and magnetite or amorphous carbon as darkening agents, and measured their reflectance by infrared spectroscopy. Measurements of these organic-rich analogues were directly compared to the VIR spectra taken from different locations around Ernutet crater. We found that the absolute reflectance of our analogues is at least two orders of magnitude higher than Ceres, but the depths of absorption bands match nicely the ones of the organic-rich Ceres spectra. The choices of the different components are discussed in comparison with VIR data. Relative abundances of the components are extrapolated from the spectra and mixture composition, considering that the differences in reflectance level is mainly due to optical effects. Absorption bands of Ceres’ organic-rich spectra are best reproduced by around 20 wt.% of carbon (a third being aliphatic carbons), in association with around 20 wt.% of carbonates, 15 wt.% of ammoniated-phyllosilicate, 20 wt.% of Mg-phyllosilicates, and 25 wt.% of darkening agent. Results also highlight the pertinence to use laboratory analogues in addition to models for planetary surface characterization. Such large quantities of organic materials near Ernutet crater, in addition to the amorphous carbon suspected on a global scale, requires a concentration mechanism whose nature is still unknown but that could potentially be relevant to other large volatile-rich bodies.
... Lacustrine carbonates in Jezero Crater also offer high preservation potential (74). A study of amino acid preservation in simulated Mars conditions found the highest preservation in smectites and sulfates (75). ...
Preprint
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An origin of Earth life on Mars would resolve significant inconsistencies between the inferred history of life and Earth's geologic history. Life as we know it utilizes amino acids, nucleic acids, and lipids for the metabolic, informational, and compartment-forming subsystems of a cell. Such building blocks may have formed simultaneously from cyanosulfidic chemical precursors in a planetary surface scenario involving ultraviolet light, wet-dry cycling, and volcanism. However, early Earth was a water world, and the timing of the rise of oxygen on Earth is inconsistent with final fixation of the genetic code in response to oxidative stress. A cyanosulfidic origin of life could have taken place on Mars via photoredox chemistry, facilitated by orders of magnitude more sub-aerial crust than early Earth, and an earlier transition to oxidative conditions. Meteoritic bombardment may have generated transient habitable environments and ejected and transferred life to Earth. The Mars 2020 Perseverance Rover offers an unprecedented opportunity to confirm or refute evidence consistent with a cyanosulfidic origin of life on Mars, search for evidence of ancient life, and constrain the evolution of Mars' oxidation state over time. We should seek to prove or refute a Martian origin for life on Earth alongside other possibilities.