Radiolysis of Nucleosides: Study of Sedimentary Microenvironment Models for the Protection of Bio-Organic Molecules on Early Earth
DOI:
https://doi.org/10.15415/jnp.2017.51010Keywords:
Chemical Evolution, Clays, Nucleosides, Ionizing RadiationAbstract
Nucleic acid bases and their derivatives are important compounds in biological systems. Many efforts have been made to demonstrate the possible prebiotic origin of these molecules, but the abiotic synthesis of these compounds has proved to be very difficult in that conditions. So, if their synthesis actually took place, a study of their stability in prebiotic conditions is quite relevant in chemical evolution studies. In this work, it has been examined and compared the influence of Sodium Montmorillonite on the chemical transformations undergone by two nucleosides (guanosine –purinic– and uridine, –pyrimidinic–) when subjected to conditions simulating the primitive Earth during the period of chemical evolution. The experiments prove the concentration capacity and protective role against external sources of ionizing radiation (specifically γ-ray) that clays can provide to these specific compounds adsorbed on them. By using X-ray diffraction, UV-vis spectrophotometry and HPLC for the analysis, it was found that purinic nucleosides (more than pyrimidinic) are quickly adsorbed on clay at low pH values, and the temperature of mineral desiccation applied after adsorption promotes their decomposition into their corresponding nitrogenous bases. In both, purinic and pyrimidinic, desorption occurs in neutral or slightly basic aqueous solutions, and both are protected by clay. Pyrimidinic nucleosides show more resistance to heat, but less resistance towards ionizing radiation, even when adsorbed in clay.
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References
Bernal JD (1951) The physical basis of life. Routledge and Kegan Paul, London, 80 p
Cairns-Smith AG, Hartman H (1988) Clay minerals and the origin of life. Cambridge University Press, Cambridge, 196 p
Draganič IG, Draganič ZD (1978). Plenary Lecture in the Second Simposium of Nuclear Chemistry, Radiochemistry and Radiations Chemistry, Mexico
Luisi, PL (1998). About various definitions of life. Origins of life and evolution of the biosphere. 28: 613-622
Mosqueira G, Albarrán G, Negrón-Mendoza A (1996) Orig Life Evol Biosph 26:75–94
Negrón-Mendoza A, Ramos-Bernal S, Mosqueira FG (2010) In: Basiuk V (ed) Astrobiology: emergence, search and detection of life. American Scientific Publishers, Los Angeles, pp 214–233
O’Donnell JH, Sangster DF (1970) Principles of radiation chemistry. American Elsevier Publishing Company, USA, p 176
Powner MW, Gerland B, Sutherland JD (2009) Nature 459:239–242
Reimann R, Zubay G (1999) Orig Life Evol Biosph 29:229–247
Zubay G (2000) Origins of life on Earth and in the cosmos Academic Press, San Diego, pp 167–250
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Journal of Nuclear Physics, Material Sciences, Radiation and Applications by Chitkara University Publications is licensed under a Creative Commons Attribution 4.0 International License. Based on a work at https://jnp.chitkara.edu.in/ |