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Last name: MEINERT
First name: Cornelia
Email: Cornelia.MEINERT@univ-cotedazur.fr
Institution: UCA
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Homochiral proteins orchestrate biological functions throughout all domains of life, but the origin of the uniform l-stereochemistry of amino acids remains unknown. Here, we describe enantioselective adsorption experiments of racemic alanine and leucine onto homochiral d- and l-quartz as a possible mechanism for the abiotic emergence of...
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In the laboratory, the photo-and thermochemical evolution of ices, made of simple molecules of astrophysical relevance, always leads to the formation of semi-refractory water-soluble organic residues. Targeted searches for specific molecules do reveal the notable presence of two families of important molecular "bricks of life": amino acids, key...
Systematic enrichments of L-amino acids in meteorites is a strong indication that biological homochirality originated beyond Earth. Although still unresolved, stellar UV circularly polarized light (CPL) is the leading hypothesis to have caused the symmetry breaking in space. This involves the differential absorption of left- and right-CPL, a...
Systematic enrichments of l -amino acids in meteorites is a strong indication that biological homochirality originated beyond Earth. Although still unresolved, stellar UV circularly polarized light (CPL) is the leading hypothesis to have caused the symmetry breaking in space. This involves the differential absorption of left- and right-CPL, a...
In the laboratory, the photo-and thermochemical evolution of ices, made of simple molecules of astrophysical relevance, always leads to the formation of semi-refractory water-soluble organic residues. Targeted searches for specific molecules do reveal the notable presence of two families of important molecular "bricks of life": amino acids, key...
The influence of protein-ligand interactions on protein stability is usually assessed by measurements in the liquid phase. CD spectroscopy appears to be a tool of choice to i) measure the conformation of the protein in different phases and to ii) follow the conformational changes of the protein upon binding.We therefore studied the stability of...
Circularly polarised light (CPL) interacting with interstellar organic molecules might have imparted chiral bias and hence preluded prebiotic evolution of biomolecular homochirality. The L-enrichment of extra-terrestrial amino acids in meteorites, as opposed to no detectable excess in monocarboxylic acids and amines, has previously been...
Carbohydrates, in particular the D-enantiomers of ribose, 2-deoxyribose, and glucose, are essential to life's informational biopolymers (RNA/DNA) and for supplying energy to living cells through glycolysis. Considered to be potential biosignatures in the search of past or present life, our capacity to detect and quantify these essential sugars...
Abstract Glycerophospholipid membranes are one of the key cellular components. Still, their species‐dependent composition and homochirality remain an elusive subject. In the context of the astrophysical circularly polarized light scenario likely involved in the generation of a chiral bias in meteoritic amino and sugar acids in space, and...
In the laboratory, the photo-and thermochemical evolution of ices, made of simple molecules of astrophysical relevance, always leads to the formation of semi-refractory water-soluble organic residues. Targeted searches for specific molecules do reveal the notable presence of two families of important molecular " bricks of life " , amino acids,...
Propylene oxide, the first chiral molecule recently detected in the interstellar medium, has once again raised the question whether biomolecular chirality might have cosmic origins. However, accurate chiroptical properties of propylene oxide in the ultraviolet spectral range necessary to suggest possible asymmetric synthetic routes in the gas...
The biomolecular homochirality in living organisms has been investigated for decades, but its origin remains poorly understood. It has been shown that circular polarized light (CPL) and other energy sources are capable of inducing small enantiomeric excesses (ees) in some primary biomolecules, such as amino acids or sugars. Since the first...
Electronic circular dichroism (ECD) and anisotropy spectra carry information on differential absorption of left- and right-circularly polarized light (LCPL and RCPL) by optically active compounds. This makes them powerful tools for the rapid determination of enantiomeric excesses (ee) in asymmetric synthetic and pharmaceutical chemistry, as...
La plus récente mission spatiale cométaire, Rosetta, était équipée d'instruments capables de caractériser les molécules organiques de la comète 67P/Tchourioumov-Guérassimenko avec une précision sans précédent. Les spectromètres de masse ont révélé une grande diversité de molécules organiques et indiquent que 67P contient à la fois des entités...
La chromatographie gazeuse monodimensionnelle (GC)est la technique de choix dans de nombreux laboratoires à travers le monde pour l'analyse de composés volatils ou semi-volatils.Toutefois, la complexité d'un grand nombre d'échantillons empêche fréquemment l'identification de tous les composés.Afin de remédier à ce manque de...
Introduction: Sugars are important molecules with high biological interest. Found in cometary-like analogs (Meinert et al., 2016), carbonaceous meteorites (Cooper et al., 2001; Furukawa et al., 2019), and likely on early Earth, sugars may have contributed as a source of molecules for the emergence of prebiotic systems on Earth. Hence, it is of...
All life on Earth is characterized by its asymmetry – both the genetic material and proteins are composed of homochiral monomers. Understanding how this molecular asymmetry initially arose is a key question related to the origins of life. Cometary ice simulations, L-enantiomeric enriched amino acids in meteorites and the detection of circularly...
How did life begin? How did the single handedness of the molecular building blocks of the complex trinity – DNA, RNA, and proteins come about? Among all the theories regarding the origin of biomolecular asymmetry, those focusing on asymmetric photochemical processes using circularly polarized light (CPL) in interstellar environments appear to...
Living organisms on the Earth almost exclusively use l-amino acids for the molecular architecture of proteins. The biological occurrence of d-amino acids is rare, although their functions in various organisms are being gradually understood. A possible explanation for the origin of biomolecular homochirality is the delivery of enantioenriched...
Gas chromatography (GC) is a separation technique commonly developed for targeted in situ analyses in planetary space missions. It is coupled with low-resolution mass spectrometry to obtain additional structural information and allow compound identification. However, ground-based analyses of extraterrestrial samples have shown the presence of...
Kuiper Belt objects exhibit a wider color range than any other solar system population. The origin of this color diversity is unknown, but likely the result of the prolonged irradiation of organic materials by galactic cosmic rays (GCRs). Here, we combine ultrahigh-vacuum irradiation experiments with comprehensive spectroscopic analyses to...
Circularly polarized light (CPL) is known to be a true chiral entity capable of generating absolute molecular asymmetry. However, the degree of inducible optical activity depends on the λ of the incident CPL. Exposure of amorphous films of rac-alanine to tunable CPL led to enantiomeric excesses (ee) which not only follow the helicity but also...