Titre :

Influence of the nature of the gas phase on the degradation of RNA during fossilization processes

Auteur(s) :

Viennet, J.-C. [Auteur]
Bernard, S. [Auteur]
Le Guillou, Corentin [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Jacquemot, P. [Auteur]
Institut de minéralogie, de physique des matériaux et de cosmochimie [IMPMC]

Delbes, L. [Auteur]
Institut de minéralogie, de physique des matériaux et de cosmochimie [IMPMC]
Balan, E. [Auteur]
Institut de minéralogie, de physique des matériaux et de cosmochimie [IMPMC]
Jaber, M. [Auteur]

Titre de la revue :

Applied Clay Science

Nom court de la revue :

Applied Clay Science

Numéro :

191

Pagination :

105616

Éditeur :

Elsevier BV

Date de publication :

2020-06

ISSN :

0169-1317

Mot(s)-clé(s) en anglais :

Biosignatures
Fossilization
RNA world
Clay minerals
Gas phase

Discipline(s) HAL :

Chimie/Matériaux
Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]
Physique [physics]/Physique [physics]/Géophysique [physics.geo-ph]
Physique [physics]/Astrophysique [astro-ph]
Planète et Univers [physics]/Astrophysique [astro-ph]
Planète et Univers [physics]/Sciences de la Terre

Résumé en anglais : [en]

The search for the most ancient traces of life on Earth has always been fraught with controversies because of the inevitable degradation undergone by fossilized biomolecules. Laboratory experiments may provide unique clues ...
Lire la suite >The search for the most ancient traces of life on Earth has always been fraught with controversies because of the inevitable degradation undergone by fossilized biomolecules. Laboratory experiments may provide unique clues to achieve a better mechanistic understanding of the key processes involving (biogenic or abiotic) organic carbon during a geological history. The Earth atmosphere has changed over geological times, from a CO2-rich atmosphere during the Hadean and Archean to the O2-rich atmosphere of the present day, with a direct impact on the nature of the gas phase trapped within the sediment porosity. Yet, the influence of the nature of this gas phase on fossilization processes has almost never been investigated. Here, we conducted a series of fossilization experiments using an emblematic biomolecule (i.e. RNA) and clay minerals at 200 °C for 7 days in closed systems in equilibrium with two different gas phases (e.g. CO2 versus N2/O2). The multiscale characterization of experimental residues using a suite of advanced microscopy and spectroscopy techniques showed that the final organo-mineral assemblages strongly depend on the nature of the gas phase. In addition to the nature of the mineral phases, results showed that the nature of the gas phase impacts the chemistry of the residual N-rich organic compounds trapped within the interlayer spaces of Mg-smectites (e.g. mainly aliphatic-rich under CO2 vs dominated by heterocycles under N2/O2). Altogether, the present study demonstrates the necessity to take into account the nature of the gas phase composition when experimentally simulating fossilization processes aiming at better constraining which biosignatures may be preserved in ancient rocks. Finally, the experimental results reported here may serve to identify the potential biosignatures that should be searched for on other planetary bodies.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Établissement(s) :

Université de Lille
CNRS
INRA
ENSCL

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Équipe(s) de recherche :

Matériaux Terrestres et Planétaires

Date de dépôt :

2021-11-18T15:10:37Z
2021-11-22T09:39:38Z