title: Meteorite-catalyzed syntheses of nucleosides and of other prebiotic compounds from formamide under proton irradiation.
abstract: Liquid formamide has been irradiated by high-energy proton beams in the presence of powdered meteorites, and the products of the catalyzed resulting syntheses were analyzed by mass spectrometry. Relative to the controls (no radiation, or no formamide, or no catalyst), an extremely rich, variegate, and prebiotically relevant panel of compounds was observed. The meteorites tested were representative of the four major classes: iron, stony iron, chondrites, and achondrites. The products obtained were amino acids, carboxylic acids, nucleobases, sugars, and, most notably, four nucleosides: cytidine, uridine, adenosine, and thymidine. In accordance with theoretical studies, the detection of HCN oligomers suggests the occurrence of mechanisms based on the generation of radical cyanide species (CN·) for the synthesis of nucleobases. Given that many of the compounds obtained are key components of extant organisms, these observations contribute to outline plausible exogenous high-energy-based prebiotic scenarios and their possible boundary conditions, as discussed.
authors: Dipartimento di Scienze Ecologiche e Biologiche, Università della Tuscia, 01100 Viterbo, Italy; ernesto.dimauro@uniroma1.it saladino@unitus.it.
authors: Raffaele
authors: R
authors: Saladino
authors: Dipartimento di Scienze Ecologiche e Biologiche, Università della Tuscia, 01100 Viterbo, Italy;
authors: Eleonora
authors: E
authors: Carota
authors: Dipartimento di Scienze Ecologiche e Biologiche, Università della Tuscia, 01100 Viterbo, Italy;
authors: Giorgia
authors: G
authors: Botta
authors: Laboratory of Radiation Biology, Joint Institute for Nuclear Research, 141980 Dubna, Russia; and.
authors: Mikhail
authors: M
authors: Kapralov
authors: Laboratory of Radiation Biology, Joint Institute for Nuclear Research, 141980 Dubna, Russia; and.
authors: Gennady N
authors: GN
authors: Timoshenko
authors: Laboratory of Radiation Biology, Joint Institute for Nuclear Research, 141980 Dubna, Russia; and.
authors: Alexei Y
authors: AY
authors: Rozanov
authors: Laboratory of Radiation Biology, Joint Institute for Nuclear Research, 141980 Dubna, Russia; and.
authors: Eugene
authors: E
authors: Krasavin
authors: Istituto Pasteur-Fondazione Cenci Bolognetti, c/o Dipartimento di Biologia e Biotecnologie "Charles Darwin," Sapienza-Università di Roma, Rome 00185, Italy ernesto.dimauro@uniroma1.it saladino@unitus.it.
authors: Ernesto
authors: E
authors: Di Mauro
mesh_terms: D000596:Amino Acids / Q000138:chemical synthesis / Q000528:radiation effects; D002264:Carboxylic Acids / Q000138:chemical synthesis / Q000528:radiation effects; D002384:Catalysis; D019418:Evolution, Chemical; D005559:Formamides / Q000737:chemistry* / Q000528:radiation effects*; D019110:Meteoroids; D008956:Models, Chemical; D015394:Molecular Structure; D009705:Nucleosides / Q000138:chemical synthesis* / Q000528:radiation effects*; D000069497:Origin of Life; D011522:Protons
chemical_list: D000596:Amino Acids; D002264:Carboxylic Acids; D005559:Formamides; D009705:Nucleosides; D011522:Protons; C031066:formamide
keywords: formamide; meteorites; nucleosides; origin of life; prebiotic syntheses