Protection of the DNA from Selected Species of Five Kingdoms in Nature by Ba(II), Sr(II), and Ca(II) Silica-Carbonates: Implications about Biogenicity and Evolving from Prebiotic Chemistry to Biological Chemistry

Mayra Cuéllar-Cruz; Selene R Islas; Norma Ramírez-Ramírez; Mario Pedraza-Reyes; Abel Moreno

doi:10.1021/acsomega.2c04170

Protection of the DNA from Selected Species of Five Kingdoms in Nature by Ba(II), Sr(II), and Ca(II) Silica-Carbonates: Implications about Biogenicity and Evolving from Prebiotic Chemistry to Biological Chemistry

ACS Omega. 2022 Oct 12;7(42):37410-37426. doi: 10.1021/acsomega.2c04170. eCollection 2022 Oct 25.

Authors

Mayra Cuéllar-Cruz¹, Selene R Islas², Norma Ramírez-Ramírez¹, Mario Pedraza-Reyes¹, Abel Moreno³

Affiliations

¹ Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta S/N, Col. Noria Alta, C.P. 36050, Guanajuato, Mexico.
² Instituto de Ciencias Aplicadas y Tecnología, Universidad Nacional Autónoma de México, Circuito Exterior S/N, Ciudad Universitaria, México City, 04510 Mexico.
³ Instituto de Química, Universidad Nacional Autónoma de México, Av. Universidad 3000, Ciudad Universitaria, México City 04510. Mexico.

Abstract

The origin of life on Earth is associated with the Precambrian era, in which the existence of a large diversity of microbial fossils has been demonstrated. Notwithstanding, despite existing evidence of the emergence of life many unsolved questions remain. The first question could be as follows: Which was the inorganic structure that allowed isolation and conservation of the first biomolecules in the existing reduced conditions of the primigenial era? Minerals have been postulated as the ones in charge of protecting theses biomolecules against the external environment. There are calcium, barium, or strontium silica-carbonates, called biomorphs, which we propose as being one of the first inorganic structures in which biomolecules were protected from the external medium. Biomorphs are structures with different biological morphologies that are not formed by cells, but by nanocrystals; some of their morphologies resemble the microfossils found in Precambrian cherts. Even though biomorphs are unknown structures in the geological registry, their similarity with some biological forms, including some Apex fossils, could suggest them as the first "inorganic scaffold" where the first biomolecules became concentrated, conserved, aligned, and duplicated to give rise to the pioneering cell. However, it has not been documented whether biomorphs could have been the primary structures that conserved biomolecules in the Precambrian era. To attain a better understanding on whether biomorphs could have been the inorganic scaffold that existed in the primigenial Earth, the aim of this contribution is to synthesize calcium, barium, and strontium biomorphs in the presence of genomic DNA from organisms of the five kingdoms in conditions emulating the atmosphere of the Precambrian era and that CO₂ concentration in conditions emulating current atmospheric conditions. Our results showed, for the first time, the formation of the kerogen signal, which is a marker of biogenicity in fossils, in the biomorphs grown in the presence of DNA. We also found the DNA to be internalized into the structure of biomorphs.