ELSI

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ELSI Seminar

Experimental approach to the adsorption and polymerization of the building blocks of life: the mineral-water interface and the dee...

Speaker
Ulysse Pedreira-Segade (ENS Lyon)
Date
July 4, 2016
Time
15:30
Room

ELSI-1 Building - 102 ELSI Hall

The abiotic formation of biologically relevant macromolecules such as DNA, RNA, proteins and lipids can be segmented into several steps leading ultimately to the emergence of life on the primitive Earth. Our group in Lyon, France, is dedicated to the study of two of these steps that are the concentration of building blocks and their polymerization.
On the one side, it has been suggested that mineral surfaces may have been of primordial importance in the local enrichment of otherwise poorly concentrated aqueous monomer species. We focused our efforts on the study of adsorption of DNA and RNA monomers, i.e. nucleotides, at the mineral-water interface of high reactive surface area phyllosilicates that may have been abundant as alteration products of the oceanic crust on the primitive Earth and we propose a model for the adsorption of DNA and RNA monomers on the surface of phyllosilicates.
On the other side, hydrothermal systems are often invoked as primitive oases for the emergence of life but their potential for the stabilization and polymerization of organic species is not fully understood. We studied the fate of the simplest and abiotically most abundant amino acid, glycine, under hydrothermal conditions using an in situ Raman spectroscopy technique coupled to diamond anvil cells.
This talk will demonstrate that the role of minerals in the concentration, stabilization and polymerization of the building blocks of life is of crucial importance, as much as the other physical and chemical parameters (pH, salinity, temperature, pressure...). Our discussion will mainly focus on the current understanding of prebiotic chemistry under hydrothermal conditions thanks to the recent progress that was made throughout the experiments carried out in Lyon.