A possible energetic role of mineral surfaces in chemical evolution

AbstractThe aim of this work is to study the behaviour of hydrogen cyanide (HCN) adsorbed onto mineral surfaces (sodium montmorillonite, a clay mineral) in different pH environments as a possible prebiotic process for complexation of organics. Our experimental results show that specific sites on the surface of the clay increased the concentration of HCN molecules dependent on the pH values. Moreover, this adsorption can occur through physical and chemical interactions enhanced by the channel structure of the sodium montmorillonite. The three-dimensional channelling structure of the clay accumulates the organics, hindering the releasing (desorption) of the organic molecules. A molecular model developed here also confirms the role of the pH as a regulating factor in the adsorption of HCN onto the inorganic surfaces and the possibility for further reactions forming more complex molecules, as an abiotic mechanism important in prebiotic chemical evolution processes.

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Stability of α-ketoglutaric acid simulating an impact-generated hydrothermal system: implications for prebiotic chemistry studies

International Journal of Astrobiology ◽

10.1017/s1473550419000302 ◽

2020 ◽

Vol 19 (3) ◽

pp. 253-259

Author(s):

L. Ramírez-Vázquez ◽

A. Negrón-Mendoza

Keyword(s):

Chemical Reactions ◽

Chemical Evolution ◽

Hydrothermal System ◽

Krebs Cycle ◽

Physicochemical Process ◽

Energy Sources ◽

Mineral Surfaces ◽

The Past ◽

The Stability

AbstractLife originated on Earth possibly as a physicochemical process; thus, geological environments and their hypothetical characteristics on early Earth are essential for chemical evolution studies. Also, it is necessary to consider the energy sources that were available in the past and the components that could have contributed to promote chemical reactions. It has been proposed that the components could have been mineral surfaces. The aim of this work is to determine the possible role of mineral surfaces on chemical evolution, and to study of the stability of relevant molecules for metabolism, such as α-ketoglutaric acid (α-keto acid, Krebs cycle participant), using ionizing radiation and thermal energy as energy sources and mineral surfaces to promote chemical reactions. Preliminary results show α-ketoglutaric acid can be relatively stable at the simulated conditions of an impact-generated hydrothermal system; thus, those systems might have been plausible environments for chemical evolution on Earth.

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A Lizardite–HCN Interaction Leading the Increasing of Molecular Complexity in an Alkaline Hydrothermal Scenario: Implications for Origin of Life Studies

Life ◽

10.3390/life11070661 ◽

2021 ◽

Vol 11 (7) ◽

pp. 661

Author(s):

Saúl A. Villafañe-Barajas ◽

Marta Ruiz-Bermejo ◽

Pedro Rayo-Pizarroso ◽

Santos Gálvez-Martínez ◽

Eva Mateo-Martí ◽

...

Keyword(s):

Chemical Evolution ◽

Hydrogen Cyanide ◽

Organic Molecule ◽

Organic Molecules ◽

Analytical Techniques ◽

Mineral Surfaces ◽

Mineral Surface ◽

Molecular Complexity ◽

Molecule Production

Hydrogen cyanide, HCN, is considered a fundamental molecule in chemical evolution. The named HCN polymers have been suggested as precursors of important bioorganics. Some novel researches have focused on the role of mineral surfaces in the hydrolysis and/or polymerization of cyanide species, but until now, their role has been unclear. Understanding the role of minerals in chemical evolution processes is crucial because minerals undoubtedly interacted with the organic molecules formed on the early Earth by different process. Therefore, we simulated the probable interactions between HCN and a serpentinite-hosted alkaline hydrothermal system. We studied the effect of serpentinite during the thermolysis of HCN at basic conditions (i.e., HCN 0.15 M, 50 h, 100 °C, pH > 10). The HCN-derived thermal polymer and supernatant formed after treatment were analyzed by several complementary analytical techniques. The results obtained suggest that: I) the mineral surfaces can act as mediators in the mechanisms of organic molecule production such as the polymerization of HCN; II) the thermal and physicochemical properties of the HCN polymer produced are affected by the presence of the mineral surface; and III) serpentinite seems to inhibit the formation of bioorganic molecules compared with the control (without mineral).

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Role of Mineral Surfaces in Prebiotic Chemical Evolution. In Silico Quantum Mechanical Studies

Life ◽

10.3390/life9010010 ◽

2019 ◽

Vol 9 (1) ◽

pp. 10 ◽

Cited By ~ 14

Author(s):

Albert Rimola ◽

Mariona Sodupe ◽

Piero Ugliengo

Keyword(s):

Chemical Evolution ◽

In Silico ◽

Density Functional ◽

Quantum Mechanical ◽

Mineral Surfaces ◽

Chemical Complexity ◽

Organic Mineral ◽

Mechanical Methods ◽

Prebiotic Chemical

There is a consensus that the interaction of organic molecules with the surfaces of naturally-occurring minerals might have played a crucial role in chemical evolution and complexification in a prebiotic era. The hurdle of an overly diluted primordial soup occurring in the free ocean may have been overcome by the adsorption and concentration of relevant molecules on the surface of abundant minerals at the sea shore. Specific organic–mineral interactions could, at the same time, organize adsorbed molecules in well-defined orientations and activate them toward chemical reactions, bringing to an increase in chemical complexity. As experimental approaches cannot easily provide details at atomic resolution, the role of in silico computer simulations may fill that gap by providing structures and reactive energy profiles at the organic–mineral interface regions. Accordingly, numerous computational studies devoted to prebiotic chemical evolution induced by organic–mineral interactions have been proposed. The present article aims at reviewing recent in silico works, mainly focusing on prebiotic processes occurring on the mineral surfaces of clays, iron sulfides, titanium dioxide, and silica and silicates simulated through quantum mechanical methods based on the density functional theory (DFT). The DFT is the most accurate way in which chemists may address the behavior of the molecular world through large models mimicking chemical complexity. A perspective on possible future scenarios of research using in silico techniques is finally proposed.

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Prebiotic studies on the interaction of zirconia nanoparticles and ribose nucleotides and their role in chemical evolution

International Journal of Astrobiology ◽

10.1017/s1473550421000033 ◽

2021 ◽

Vol 20 (2) ◽

pp. 142-149

Author(s):

Avnish Kumar Arora ◽

Pankaj Kumar

Keyword(s):

Electron Microscopy ◽

Metal Oxide ◽

Metal Oxides ◽

Chemical Evolution ◽

Ribonucleic Acid ◽

Zirconium Oxide ◽

Origins Of Life ◽

Neutral Ph ◽

Interaction Studies

AbstractStudies on the interaction of biomolecules with inorganic compounds, mainly mineral surfaces, are of great concern in identifying their role in chemical evolution and origins of life. Metal oxides are the major constituents of earth and earth-like planets. Hence, studies on the interaction of biomolecules with these minerals are the point of concern for the study of the emergence of life on different planets. Zirconium oxide is one of the metal oxides present in earth's crust as it is a part of several types of rocks found in sandy areas such as beaches and riverbeds, e.g. pebbles of baddeleyite. Different metal oxides have been studied for their role in chemical evolution but no studies have been reported about the role of zirconium oxide in chemical evolution and origins of life. Therefore, studies were carried out on the interaction of ribonucleic acid constituents, 5′-CMP (cytidine monophosphate), 5′-UMP (uridine monophosphate), 5′-GMP (guanosine monophosphate) and 5′-AMP (adenosine monophosphate), with zirconium oxide. Synthesized zirconium oxide particles were characterized by using vibrating sample magnetometer, X-Ray Diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy. Zirconia particles were in the nanometre range, from 14 to 27 nm. The interaction of zirconium oxide with ribonucleic acid constituents was performed in the concentration range of 5 × 10−5–300 × 10−5 M. Interaction studies were carried out in three mediums; acidic (pH 4.0), neutral (pH 7.0) and basic (pH 9.0). At neutral pH, maximum interaction was observed. The interaction of zirconium oxide with 5′-UMP was 49.45% and with 5′-CMP 67.98%, while with others it was in between. Interaction studies were Langmurian in nature. Xm and KL values were calculated. Infrared spectral studies of ribonucleotides, metal oxide and ribonucleotide–metal oxide adducts were carried out to find out the interactive sites. It was observed that the nitrogen base and phosphate moiety of ribonucleotides interact with the positive charge surface of metal oxide. SEM was also carried out to study the adsorption. The results of the present study favour the important role of zirconium oxide in concentrating the organic molecules from their dilute aqueous solutions in primeval seas.

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