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Prebiotic Chemistry and the Origin of Life. The possible role of UV radiation

Prebiotic Chemistry and the Origin of Life. The possible role of UV radiation. Claudia Crestini , Dipatimento di Scienze e Tecnologie Chimiche, Tor Vergata University, Rome, Italy Raffaele Saladino , Dipartimento di Agrobiologia ed Agrochimica, Università della Tuscia, Viterbo, Italy.

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Prebiotic Chemistry and the Origin of Life. The possible role of UV radiation

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  1. Prebiotic Chemistry and the Origin of Life. The possible role of UV radiation Claudia Crestini, Dipatimento di Scienze e Tecnologie Chimiche, Tor Vergata University, Rome, Italy Raffaele Saladino, Dipartimento di Agrobiologia ed Agrochimica, Università della Tuscia, Viterbo, Italy.  WUTA08
1st Italian Workshop on UltraViolet Techniques and Applications

  2. The RNA World Hypothesis Joyce, G.F. (2002) Nature 418, 214-221. • Prebiotic chemistry: synthesis of biological molecules necessary for the birth of the first living cell • Origin of informational polymers  Claudia Crestini - WUTA08

  3. Heterotrophic theory • A primordial soup of simple molecules arose first • driven by non biological energy like radiation or heat • assembled in complex molecules and • led to primitive life forms  Claudia Crestini - WUTA08

  4. A heterotrophic origin of life? Reducing atmosphere Biomolecules synthesis Prebiotic soup Complex molecules  Claudia Crestini - WUTA08

  5. Formamide as prebiotic probe “Simulations based on Density Functional Theory show that formamide is the most stable species with molecular formula “CHON” Pauzat, F. et al. 6th EANA 2006 “This one-carbon molecule was detected in the gas phase of interstellar medium” Crovisier, J. Astrobiology: Future Perspectives, Kluwer Eds, 2004 Chapter 8, p. 179-203. “in the long period comet Hale-Bopp“ Bockelee-Morvan,D. et al. Astr. Astrophys. 2000 “and tentatively in the solid phase on grains around the young stellar object W33A “ W.A. Schutte et al. Astr. Astrophys. 1999  Claudia Crestini - WUTA08

  6. Formamide. Phisical and Chemical properties “Formamide has a high boiling point, without azeotropic effects, and a wide range of uses as a solvent. It has an efficient solubilizing effect on nucleobases, nucleosides, nucleotides, amino acids, proteins, sugars, metalsand salts” Becker, B. J. Chem. Eng. 1970 Colloids and surfacesA: Physicochem Eng. Aspects 2003 219: 281-290. A comparison of micelle formation of ionic surfactants in formamide, in N-methylformamide and in N, N-dimethylformamide. M.Salim Akhter, Sadeq M. Alawi Langmuir. 2004 Jan 20;20(2):329-35. Solvation dynamics of formamide and N, N-dimethylformamide in aerosol OT reverse micelles. Shirota H, Segawa H.  Claudia Crestini - WUTA08

  7. Elemental formamide chemistry (C) (D) (A) (B)  Claudia Crestini - WUTA08

  8. The mineral Honeycomb Role of minerals metals and metal oxides in prebiotic chemistry  Claudia Crestini - WUTA08

  9. The role of minerals and metal oxides on prebiotic processes. A general overview • Minerals can accumulate the prebiotic precursors (concentration effect) • Minerals can act as catalytic environments, reducing the activation energy for the formation of products • Minerals can tune the selectivity of prebiotic syntheses • Minerals may act as a template • Minerals are benign environments to preserve newly formed biomolecules from degradation  Claudia Crestini - WUTA08

  10. Bioorganic Med. Chem. 9 (2001) 1249-1253A Possible Prebiotic Synthesis of Purine, Adenine, Cytosine, and 4(3H)-Pyrimidinone From Formamide: Implications for the Origin of LifeRaffaele Saladino,Claudia Crestini, Giovanna Costanzo, Rodolfo Negriand Ernesto Di Mauro  Claudia Crestini - WUTA08

  11. Analyzing the reaction mechanism. 13C/15N-NMR Experiments “route of the purine ring”  Claudia Crestini - WUTA08

  12. Analyzing the reaction mechanism. “route of the pyrimidine ring”  Claudia Crestini - WUTA08

  13. Toward an extraterrestrial synthesis of nucleobases Draco constellation Anselm Kiefer High Museum of Art Atlanta, USA

  14. Cosmic dust  Claudia Crestini - WUTA08

  15. Cosmic dust analogues preparation (Fayalite) Fe2SiO4* 1) Mg0.5Fe1.5SiO4 * 2) 3) MgFeSiO4 * (Olivine) SiO2, MgO, FeO2 Mg1.5Fe0.5 SiO4 * 4) Laser Ablation 5) Mg2SiO4 * (Fosferite) Cosmic dust analogue olivines (Mg,Fe)2SiO4 are synthesized by laser ablation technique (Nd-YAG 108 Wcm-2). Oxide pellets of MgO, FeO2, SiO2 are used as laser target vaporized in 10 mbar atmosphere of O2. Brucato, J. R. et al in The Astronomy and Astrophysics Review, Volume 11, Issue 2-3, pp. 97-152 (2003)  Claudia Crestini - WUTA08

  16. olivine ChemBioChem 6 (2005) 1368-1374 Synthesis and Degradation of Nucleic Acid Components by Formamide and Cosmic Dust Analogues Raffaele Saladino,Claudia Crestini, Veronica Neri,John R. Brucato,Luigi Colangeli,Fabiana Ciciriello, Giovanna Costanzo, and Ernesto Di Mauro Fe Si Mg CDAs qualitative composition fayalite forsterite DHU:5,6-DiHydroUracil  Claudia Crestini - WUTA08

  17. Fe Si Mg olivine fayalite forsterite ChemBioChem 6 (2005) 1368-1374 Synthesis and Degradation of Nucleic Acid Components by Formamide and Cosmic Dust Analogues Raffaele Saladino,Claudia Crestini, Veronica Neri,John R. Brucato,Luigi Colangeli,Fabiana Ciciriello, Giovanna Costanzo, and Ernesto Di Mauro Yield defined as mg of product per gram of formamide. mg/g  Claudia Crestini - WUTA08

  18. Moving towards nucleosides

  19. ChemBioChem 4 (2003) 514-521 One-pot TiO2-Catalyzed Synthesis of Nucleic Bases and Acyclonucleosides From Formamide: Implications for the Origin of Life Raffaele Saladino,a,* Claudia Crestini,b Umberto Ciambecchini,a Rodolfo Negri,c Giovanna Costanzo,c Ernesto Di Mauro c, Adenine, cytosine and thymine 3 acyclonucleosides  Claudia Crestini - WUTA08

  20. Thymine synthetic pathway R. H. Barker, 1975 Unic known one pot synthesis of thymine!  Claudia Crestini - WUTA08

  21. Thymine from formamide Formamide Present day biosynthesis of thymidine  Claudia Crestini - WUTA08

  22. Nucleosides from formamide Compd 9 Compd 10  Claudia Crestini - WUTA08 Compd 11

  23. Sugars synthetic pathway. The formose reaction. Butlerow, 1861. Single headed arrows represent aldol Condensations. Double-headed arrows represent enolizations. Aldotreose can undergo a reverse aldol condensation  Claudia Crestini - WUTA08

  24. A novel formose reaction Unic known prebiotic syntesis of nucleosides!  Claudia Crestini - WUTA08

  25. Exploring the role of UV-radiation in prebiotic chemistry

  26. UV radiation in prebiotic chemistry. Pioneering studies Diamminomalononitril cyclization to a key imidazole intermediate  Claudia Crestini - WUTA08

  27. UV radiation in prebiotic chemistry. Pyrimidine From Cyanoacetaldehyde hn Double bond isomerization for cytosine ring closure 30-50% yield M. P. Robertson, S. L. Miller Nature 1995, 972.  Claudia Crestini - WUTA08

  28. UV radiation in prebiotic chemistry. Glyoxal From formaldehyde H. Mordehai BioSystems 1979, 11(4), 227-32  Claudia Crestini - WUTA08

  29. Exploring the role of UV-radiation onformamide prebiotic chemistry

  30. Photocatalysis and the origin of life: Synthesis of nucleoside bases from Formamide on TiO2(001) single surface. Senanayake, S. D. and Idriss, H. (2006) PNAS. USA 103 Uncorrected peak areas of desorbing products The surface structures of TiO2 (001) single crystal

  31. Exploring the role of UV-radiation on formamide prebiotic chemistry our interest is to develop novel prebiotic chemistry of nucleic acids based on formamide under uv irradiation in the presence of minerals or selected organic compounds that can act as photocatalysts. we hope that the syncrotron facility can be used for this novel approach to esobiology  Claudia Crestini - WUTA08

  32. Thank you for the kind attention!

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