New Insights about Equilibrium Constants, pKa, of Purine Nitrogenous Bases: The Case of Adenine and Guanine. A UV-Vis Spectrophotometric Study at I = 0.4 M
DOI:
https://doi.org/10.29356/jmcs.v69i1.2292Keywords:
Adenine, Guanine, pKa, UV-Vis, SQUADAbstract
In the present work, novel experimental evidence about acidity constants has been found for adenine and guanine in aqueous medium. Despite being molecules widely studied there is some inconsistences about their chemical speciation in the literature. The study that we presented by UV-Vis spectrophotometry and subsequent data processing using the SQUAD software allowed the determination of three acidity constants for both adenine (pKa1 = 3.361± 0.102, pKa2 = 9.056 ± 0.091 y pKa3 = 10.132 ± 0.057) and guanine (pKa1 = 3.402± 0.028, pKa2 = 9.708 ± 0.022 y pKa3 = 12.721 ± 0.015) at ionic strength 0.4 M and T = (25.0 ± 0.1) °C. Being theses bases fundamental components of DNA and RNA, it is relevant to know in depth their physicochemical properties to improve the understanding of the biological processes involved in the transmission of genetic information, as well as their implications in medicine, biotechnology and molecular biology.
Resumen. En el presente trabajo se muestra evidencia experimental novedosa de las constantes de acidez de la adenina y de la guanina en medio acuoso. A pesar de ser moléculas ampliamente estudiadas existen algunas inconsistencias reportadas en la literatura acerca de su especiación química. El estudio por espectrofotometría de UV-Vis y posterior tratamiento de datos usando el software SQUAD permitió determinar tres constantes de acidez tanto para la adenina (pKa1 = 3.361± 0.102, pKa2 = 9.056 ± 0.091 y pKa3 = 10.132 ± 0.057) como para la guanina (pKa1 = 3.402± 0.028, pKa2 = 9.708 ± 0.022 y pKa3 = 12.721 ± 0.015) a fuerza iónica 0.4 M y T = (25.0 ± 0.1) °C. Dado que estas bases nitrogenadas son componentes fundamentales del ADN y del ARN, es relevante conocer a profundidad sus propiedades fisicoquímicas para mejorar nuestro entendimiento en los procesos biológicos donde estas bases se encuentran involucradas por ejemplo; en la transmisión de información genética así como sus implicaciones en campos como la medicina, biotecnología y la biología molecular.
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References
Balanikas, E.; Banyasz, A.; Douki, T.; Baldacchino, G.; Markovitsi, D. Acc. Chem. Res. 2020, 53, 1511-1519.
Guo, H.; Zhang, T.; Wang, M.; Sun, L.; Zhang, J.; Yang, M.; Yang, F.; Wu, N.; Yang, W. Colloids Surf. A. 2021, 627, 127195.
Weimann, A.; Belling, D.; Poulsen, H. E. Nucleic Acids Res. 2022, 30, 1-8.
Shih, Y. M.; Cooke, M.; Pan, C. H.; Chao, M. R.; Hu, C. W. Redox Biol. 2019, 20, 556-565.
El-Maali, N. A.; Wang, J. Sens Actuators B Chem. 2001, 76, 211.
Abbaspour, A.; Mehrgardi, M. A. Anal. Chem. 2004, 76, 5690-5696.
Martínez-Guerra, J. ; Rojas-Hernández, A.; Guzmán-Hernández, D. S.; Palomar-Pardavé, M.; Romero-Romo, M.; Ramírez-Silva, M. T. ECS Trans. 2023, 110, 199-205.
Verdolino, V.; Cammi, R.; Munk, B. H.; Schlegel, H. B. J. Phys. Chem B. 2008, 112, 16860-16877.
Acharya, P.; Cheruku, P.; Chatterjee, S.; Acharya, S.; Chattopadhyaya, J. J. Am. Chem. Soc. 2004, 126, 2862-2869.
Dawson, R. M. C.; Elliott, D. C.; Elliot, W. H.; Jones, K. M. in: Data for Biochemical Research, Research. Ed., Oxford University, Press: Oxford, 1986.
Jang, Y. H.; Goddard, W. A.; Noyes, K. T.; Sowers, L. C.; Hwang, S.; Chung, D. S. Chem. Res. Tox. 2002, 15, 1023-1035.
Fasman, G. D. in: CRC Handbook of Biochemistry and Molecular Biology, Nucleic Acids. Ed., CRC Press, Cleveland, OH, 1975.
Jordan, D. O. in: The Chemistry of Nucleic Acids. Ed. London, 1960.
Chargaff, E.; Davidson, J. N. in: The Nucleic Acids Chemistry and Biology, Ed., Academic Press: New York, 1955.
Budavari, S. The Merck Index, 12th Ed., Merck and Company: Whitehouse Station, NJ, 1996.
Jang, Y. H.; Goddard, W. A.; Noyes, K. T.; Sowers, L. C.; Hwang, S.; Chung, D. S. J. Phy. Chem. B. 2003, 107, 344-357.
Leggett, D.J.; McBryde, W.A.E. in: Anal. Chem. 1975, 47,1065-1070.
Martínez-Guerra, J.; Palomar-Pardavé, M.; Romero-Romo, M.; Corona-Avendaño, S.; Rojas-Hernández, A.; Ramírez-Silva, M. T. Int. J. Electrochem. Sci. 2019, 14, 5373-5385.
Martínez-Guerra, J.; Palomar-Pardavé, M.; Romero-Romo, M.; Corona-Avendaño, S.; Guzmán-Hernández, D. S.; Rojas-Hernández, A.; Ramírez-Silva, M. T. ChemElectroChem. 2022, 9, 1-9.
Rojas-Hernández, A.; Ramírez, M. T.; González, I.; Ibáñez, J. G. J. Chem. Educ. 1995, 72, 1099-1105.
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