Investigations into the chemical origin of life have recently benefitted from a holistic approach in which possible atmospheric, organic, and inorganic systems chemistries are taken into consideration. In this way, we now report that a selective phosphate activating agent, namely methyl isocyanide, could plausibly have been produced from simple prebiotic feedstocks. We show that methyl isocyanide drives the conversion of nucleoside monophosphates to phosphorimidazolides under potentially prebiotic conditions and in excellent yields for the first time. Importantly, this chemistry allows for repeated reactivation cycles, a property long sought in nonenzymatic oligomerization studies. Further, as the isocyanide is released upon irradiation, the possibility of spatially and temporally controlled activation chemistry is thus raised.

Since the pioneering work of Emanuel Gil‐Av and his associates at the Weizmann Institute of Science the direct gas chromatographic resolution of enantiomers has found its application in different fields of natural sciences, even expanding to space research and astrobiology. In these domains the resolution of chiral molecules of prebiotic relevance is of particular interest, since the determination of ratios between l‐ and d‐enantiomers within non‐terrestrial samples is assumed to shed light on the origin of biomolecular homochirality and the beginnings of life itself. According to an astrophysical scenario, the first molecular symmetry breaking event occurred upon irradiation of chiral organic molecules with circularly polarized light present in the interstellar medium. To examine this hypothesis, among others, chiral gas chromatographic stationary phases have been widely used to provide the differentiation of enantiomers in extracts of meteorites, samples of simulated interstellar ices and Mars soil analogues. Moreover several chiral capillary columns have been selected for in situ analyses of extraterrestrial organic matter by Mars missions and the cometary Rosetta mission. This review will highlight current advances of enantioselective gas chromatography applied to space science.

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Context. Carbonaceous chondrites are sources of information on the origin of the Solar System. Their organic content is conventionally classified as soluble (SOM) and insoluble organic matter (IOM), where the latter represents the majority. Aims. In this work, our objectives are to identify possible relations between soluble and insoluble organic matter generated in laboratory experiments and to extrapolate the laboratory analog findings to soluble and insoluble organic matter of meteorites to test their connection. Methods. Using laboratory experiments, processes possibly linking IOM analog (IOMA) to SOM analog (SOMA) precursors are investigated by assuming that dense molecular ices are one of the sources of organic matter in the Solar System. Each organic fraction is analyzed by laser desorption coupled to a Fourier transform ion cyclotron resonance mass spectrometer on a comprehensive basis. Results. SOMA and IOMA significantly differ in their chemical fingerprints, and particularly in their aromaticity, O/C, and N/C elemental ratios. Using an innovative molecular network, the SOMA-IOMA transition was tested, revealing connection between both classes. This new network suggests that IOMA is formed in two steps: a first generation IOMA based on precursors from SOMA, while a second IOMA generation is formed by altering the first IOMA generation. Finally, using the same analytical technique, the molecular content of IOMA and that of the Paris IOM are compared, showing their molecular similarities for the first time. The molecular network application to the Paris SOM and IOM demonstrates that a possible connection related to photochemical ice processing is present, but that the overall history of IOM formation in meteorites is much more complex and might have been affected by additional factors (e.g., aqueous alteration). Conclusions. Our approach provides a new way to analyze the organic fraction of extraterrestrial material, giving new insights into the evolution of organic matter in the Solar System.