Characterization of the Adsorption of Nucleic Acid Bases onto Ferrihydrite via Fourier Transform Infrared and Surface-Enhanced Raman Spectroscopy and X-ray Diffractometry

Abstract

Minerals could have played an important role in concentration, protection, and polymerization of biomolecules. Although iron is the fourth most abundant element in Earth's crust, there are few works in the literature that describe the use of iron oxide-hydroxide in prebiotic chemistry experiments. In the present work, the interaction of adenine, thymine, and uracil with ferrihydrite was studied under conditions that resemble those of prebiotic Earth. At acidic pH, anions in artificial seawater decreased the pH at the point of zero charge (pHpzc) of ferrihydrite; and at basic pH, cations increased the pHpzc. The adsorption of nucleic acid bases onto ferrihydrite followed the order adenine >> uracil > thymine. Adenine adsorption peaked at neutral pH; however, for thymine and uracil, adsorption increased with increasing pH. Electrostatic interactions did not appear to play an important role on the adsorption of nucleic acid bases onto ferrihydrite. Adenine adsorption onto ferrihydrite was higher in distilled water compared to artificial seawater. After ferrihydrite was mixed with artificial seawaters or nucleic acid bases, X-ray diffractograms and Fourier transform infrared spectra did not show any change. Surface-enhanced Raman spectroscopy showed that the interaction of adenine with ferrihydrite was not pH-dependent. In contrast, the interactions of thymine and uracil with ferrihydrite were pH-dependent such that, at basic pH, thymine and uracil lay flat on the surface of ferrihydrite, and at acidic pH, thymine and uracil were perpendicular to the surface. Ferrihydrite adsorbed much more adenine than thymine; thus adenine would have been better protected against degradation by hydrolysis or UV radiation on prebiotic Earth.

Effect of γ-radiation on adenine dissolved in distilled water, saline solutions and artificial seawater resembling that of 4.0 billion years ago

“…Of course, control experiments (in distilled water) are necessary to provide an idea of the effect of the ions. We observed that this seawater influences the stability of minerals and the adsorption of nucleic acid bases (Anizelli et al ., 2015, 2016; Canhisares-Filho et al ., 2015; Carneiro et al ., 2017; Villafañe-Barajas et al ., 2018; Zaia et al ., 2018). In addition, the interaction of cations of seawater (Ca 2+ , Mg 2+ , Sr 2+ and Na + ) with nucleic acid bases changed their reactivity (Anizelli et al ., 2014; Baú et al ., 2019).…”

“…Based on the work of Izawa et al (2010), who performed an experiment through leaching of meteorite samples in Tagish Lake, Zaia (2012) suggested a model of artificial seawater. For several years our group has been working with this artificial seawater model, which probably better resembles the major ions of the ocean of the prebiotic Earth (Anizelli et al, 2014(Anizelli et al, , 2015(Anizelli et al, , 2016Canhisares-Filho et al, 2015;Carneiro et al, 2017;Villafañe-Barajas et al, 2018;Zaia et al, 2018;Baú et al, 2019). Unlike the seawater in the oceans today that have a high concentration of Na + and Cl − (Bearman, 2004), this artificial seawater contains high concentrations of Mg 2+ and SO 4 2− (Zaia, 2012).…”

Study of the formation of ferrihydrite under prebiotic chemistry conditions: artificial seawater 4.0 Gy and ammonium thiocyanate

“…Thus, in such environments, ferrihydrite could be synthesized and maybe an intermediary for the synthesis of hematite, goethite and lepidocrocite (Rzepa et al, 2016;Bassez, 2018). In addition to a number of applications in science and technology (Cornell and Schwertmann, 2003), several iron oxides have been used in prebiotic chemistry experiments such as sorption of biomolecules or precursors of biomolecules (Matrajt and Blanot, 2004;Vieira et al, 2011;Shanker et al, 2013;Canhisares-Filho et al, 2015;Farias et al, 2016;Zaia et al, 2020), catalyzation of the formation of biomolecules (Shanker et al, 2011;Bizzarri et al, 2018;Barge et al, 2019) and catalysation of the formation of biopolymers (Matrajt and Blanot, 2004;Shanker et al, 2012;Georgelin et al, 2017).…”

Mineral Facilitated Horizontal Gene Transfer: A New Principle for Evolution of Life?

“…The longevity of mineral adsorbed DNA depends on a range of factors where in particular mineral species ( Lorenz and Wackernagel, 1987 ; Cao et al, 2011 ; Michalkova et al, 2011 ; Feuillie et al, 2013 ; Canhisares-Filho et al, 2015 ; Pedreira-Segade et al, 2016 ), background ions ( Lorenz and Wackernagel, 1987 ; Nguyen and Chen, 2007 ; Lu et al, 2010 ), salinity, and pH ( Greaves and Wilson, 1969 ; Saeki et al, 2010 ; Michalkova et al, 2011 ; Feuillie et al, 2015 ; Maity et al, 2015 ) determine the DNA adsorption capacity of a mineral. Depending on the crystalline structure and composition, the surface charge of most minerals changes as a function of pH.…”