Laura Patricia Cruz-Cruz, Sciences Faculty, National Autonomous University of Mexico (UNAM), Mexico City-04520, Mexico
Alicia Negrón-Mendoza and Alejandro Heredia-Barbero, Department of Radiation Chemistry and Radio chemistry, Institute of Nuclear Sciences, National Autonomous University of Mexico (UNAM), Mexico City-04520, Mexico
Chemical evolution, Glycine, Saline water, Ionizing radiation
The stability of biologically important molecules, such as amino acids, being subjected to highradiation fields is relevant for chemical evolution studies. Bodies of water were very important in the primitive Earth. In these bodies, the presence of dissolved salts, together with organic molecules, could influence the behavior of the systems in prebiotic environments.
The objective of this work is to examine the influence of sodium chloride on the stability of the amino acid glycine when subjected to high radiation doses. The analysis of the irradiated samples was followed by HPLC coupled with a UV-VIS detector. The results show that glycine in aqueous solutions (without oxygen) decomposed around 90% at a dose of 91 kGy. In the presence of salts, up to 80% of the amino acid was recovered at the same dose. Laboratory simulations demonstrate a protective role for sodium chloride (specifically the chloride ion) to glycine against an external source of ionizing radiation.
A. Negrón-Mendoza and G. Albarran. Chemical Evolution. Origin of life, 147–235 (1993).
J. Cruz-Castañeda, A. Negrón-Mendoza, D. Frías, M. Colín-García, A. Heredia, S. Ramos-Bernal and S. Villafañe-Barajas, J Radioanal Nucl. Chem. 304, 219–225 (2015). https://doi.org/10.1007/s10967-014-3711-z
Garzón, L., and M. L. Garzón, Origins of Life and Evolution of the Biosphere 31, 3 (2001). https://doi.org/10.1023/A:1006664230212
J. W. T. Spinks and R. J. Woods, Introduction to Radiation Chemistry. (John Wiley and Sons, Inc., New York, 1990).
S. J. Mojzsis, T. M. Harrison and R. T. Pidgeon, Nature 409, 178 (2001). https://doi.org/10.1038/35051557
W. H. Peck, J. W. Valley, S. A. Wilde and C. M. Graham, Geochimica et Cosmochimica Acta 65, 4215 (2001). https://doi.org/10.1016/S0016-7037(01)00711-6
R. F. Weiss, Deep Sea Research and Oceanographic Abstracts 17, 721 (1970). https://doi.org/10.1016/0011-7471(70)90037-9
S. A. Hassan, J Phys Chem B 109, 21989 (2005). https://doi.org/10.1021/jp054042r
D. A. M. Zaia, C. T. B. V. Zaia and H. De Santana, Origins of Life and Evolution of Biospheres 38, 469 (2008). https://doi.org/10.1007/s11084-008-9150-5