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1.
Acc Chem Res ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39141709

RESUMEN

ConspectusThe origin of life remains one of the most profound mysteries in science. Over millennia, theories have evolved, yet the question persists: How did life emerge from inanimate matter? At its core, the study of life's origin offers insights into our place in the universe and the nature of life itself. By delving into the chemical and geological processes that led to life's emergence, scientists gain a deeper understanding of the fundamental principles that govern living systems. This knowledge not only expands our scientific understanding but also has profound implications for fields ranging from astrobiology to synthetic biology.This research employs a multidisciplinary approach, combining a diverse array of techniques, from space missions to wet laboratory experiments to theoretical modeling. Investigations into the formation of the first proto-biomolecules are tailored to explore both the complex molecular processes that underpin life and the geological contexts in which these processes may have occurred. While laboratory experiments are aimed at mimicking the processes of early planets, not every process and sample is attainable. To this end, we demonstrate the use of molecular modeling techniques to complement experimental efforts and extraterrestrial missions. The simulations enable researchers to test hypotheses and explore scenarios that are difficult or impossible to replicate in the laboratory, bridging gaps in our understanding of prebiotic processes across vast time and space scales.Minerals, particularly layered structures like clays and hydrotalcites, play diverse and pivotal roles in the origin of life. They concentrate organic species, catalyze polymerization reactions (such as peptide formation), and provide protective environments for the molecules. Minerals have also been suggested to have acted as primitive genetic materials. Nevertheless, they may lack the ability for long-term information replication. Instead, we suggest that minerals may act as transcribers of information encoded in environmental cyclic phenomena, such as tidal or seasonal changes. We argue that extensive protection of the produced polymer will immobilize it, making it inactive for any further function. Therefore, in order to generate a functional polymer, it is essential that it remains mobile and chemically active. Furthermore, we suggest a route to the identification of pseudobiosignatures, a polymer that was polymerized on the same mineral surface and consequently retained through overprotection.This Account presents a comprehensive evaluation of the current understanding of the role of layered mineral surfaces on life's origin and biosignature preservation. It highlights the complexity of mineral-organic interactions and proposes pathways for proto-biomolecule emergence and methods for identifying and interpreting potential biosignatures. Ultimately, the quest to uncover the origin of life continues to drive scientific exploration and innovation, offering profound insights into the fundamental nature of existence and our place in the universe.

2.
J Am Chem Soc ; 146(27): 18360-18369, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38935813

RESUMEN

2H solid-state NMR and atomistic molecular dynamics (MD) simulations are used to understand the disorder of guest solvent molecules in two cocrystal solvates of the pharmaceutical furosemide. Traditional approaches to interpreting the NMR data fail to provide a coherent model of molecular behavior and indeed give misleading kinetic data. In contrast, the direct prediction of the NMR properties from MD simulation trajectories allows the NMR data to be correctly interpreted in terms of combined jump-type and libration-type motions. Time-independent component analysis of the MD trajectories provides additional insights, particularly for motions that are invisible to NMR. This allows a coherent picture of the dynamics of molecules restricted in molecular-sized cavities to be determined.

3.
ACS Nano ; 16(10): 16109-16117, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36166830

RESUMEN

The scalable production and dispersion of 2D materials, like graphene, is critical to enable their use in commercial applications. While liquid exfoliation is commonly used, solvents such as N-methyl-pyrrolidone (NMP) are toxic and difficult to scale up. However, the search for alternative solvents is hindered by the intimidating size of the chemical space. Here, we present a computational pipeline informing the identification of effective exfoliation agents. Classical molecular dynamics simulations provide statistical sampling of interactions, enabling the identification of key molecular descriptors for a successful solvent. The statistically representative configurations from these simulations, studied with quantum mechanical calculations, allow us to gain insights onto the chemophysical interactions at the surface-solvent interface. As an exemplar, through this pipeline we identify a potential graphene exfoliation agent 2-pyrrolidone and experimentally demonstrate it to be as effective as NMP. Our workflow can be generalized to any 2D material and solvent system, enabling the screening of a wide range of compounds and solvents to identify safer and cheaper means of producing dispersions.

4.
Molecules ; 27(14)2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35889463

RESUMEN

Hydrocarbon vapor adsorption experiments (HVAs) are one of the most prevalent methods used to evaluate the proportion of adsorbed state oil, critical in understanding the recoverable resources of shale oil. HVAs have some limitations, which cannot be directly used to evaluate the proportion of adsorbed state oil. The proportion of adsorbed state oil from HVA is always smaller than that in shale oil reservoirs, which is caused by the difference in adsorption characteristics of liquid and gaseous hydrocarbons. The results of HVA need to be corrected. In this paper, HVA was conducted with kaolinite, an important component of shale. A new method is reported here to evaluate the proportion of adsorbed state oil. Molecular dynamics simulations (MDs) of gaseous/liquid hydrocarbons with the same temperature and pressure as the HVAs were used as a reference to reveal the errors in the HVAs evaluation from the molecular scale. We determine the amount of free state of hydrocarbons by HVAs, and then calculate the proportion of adsorbed state oil by the liquid hydrocarbon MD simulation under the same conditions. The results show that gaseous hydrocarbons adsorptions are monolayer at low relative pressures and bilayer at high relative pressures. The liquid hydrocarbons adsorption is multilayer adsorption. The adsorption capacity of liquid hydrocarbons is over 2.7 times higher than gaseous hydrocarbons. The new method will be more effective and accurate to evaluate the proportion of adsorbed state oil.


Asunto(s)
Gases , Hidrocarburos , Adsorción , Caolín , Minerales , Yacimiento de Petróleo y Gas
5.
Life (Basel) ; 10(3)2020 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-32110893

RESUMEN

Research on the origin of life is highly heterogeneous. After a peculiar historical development, it still includes strongly opposed views which potentially hinder progress. In the 1st Interdisciplinary Origin of Life Meeting, early-career researchers gathered to explore the commonalities between theories and approaches, critical divergence points, and expectations for the future. We find that even though classical approaches and theories-e.g. bottom-up and top-down, RNA world vs. metabolism-first-have been prevalent in origin of life research, they are ceasing to be mutually exclusive and they can and should feed integrating approaches. Here we focus on pressing questions and recent developments that bridge the classical disciplines and approaches, and highlight expectations for future endeavours in origin of life research.

6.
Chem Commun (Camb) ; 54(35): 4394-4397, 2018 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-29537012

RESUMEN

We describe a novel post treatment for layered double hydroxide (LDH) materials using aqueous immiscible (AIM) solvents resulting in improved surface area and powder flow. The effect of solvent functional groups and structure is explored, aided by molecular dynamics simulation of AIM-LDH washing.

7.
Nat Commun ; 8(1): 2033, 2017 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-29229963

RESUMEN

Some seventy years ago, John Desmond Bernal proposed a role for clays in the origin of life. While much research has since been dedicated to the study of silicate clays, layered double hydroxides, believed to be common on the early Earth, have received only limited attention. Here we examine the role that layered hydroxides could have played in prebiotic peptide formation. We demonstrate how these minerals can concentrate, align and act as adsorption templates for amino acids, and during wetting-drying cycles, promote peptide bond formation. This enables us to propose a testable mechanism for the growth of peptides at layered double hydroxide interfaces in an early Earth environment. Our results provide insights into the potential role of mineral surfaces in mimicking aspects of biochemical reaction pathways.


Asunto(s)
Hidróxidos/química , Minerales/química , Origen de la Vida , Péptidos/química , Silicatos de Aluminio/química , Aminoácidos/química , Arcilla , Planeta Tierra , Propiedades de Superficie
8.
J Mol Model ; 17(1): 21-6, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20349355

RESUMEN

The mechanism for the decarbonylation of (E)-2-butenal and (E)-2-methyl-3-phenyl-2-propenal was studied with different levels of ab initio and DFT methods. Reactants, products and transition structures were optimized for two kinds of reaction channel: a one-step reaction which involves a three-membered cyclic transition state, and a two-step reaction which involves an initial four-membered cyclic transition state. According to our calculations, these two possible mechanisms entail similar energetic costs, and there are only small differences depending on the reactant. The elimination of (E)-2-methyl-3-phenyl-2-propenal yields different products depending on the channel followed. Only one of the three possible one-step mechanisms leads directly to (E)-ß-methylstyrene (the main product according to experiment). This fact is reasonably well reproduced by our results, since the corresponding transition state gave rise to the lowest activation Gibbs free energy.


Asunto(s)
Aldehídos/química , Gases/química
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