New Directions for an Experimental Approach to the Chemistry of the Origin of Life
Résumé
Organic matter is formed in molecular clouds from which planetary systems arise as well as in planetary environments. Most of these locations are not likely to harbour life, questioning the genuine prebiotic character of the corresponding chemistry and its relevance to the origin of life. The formation of organic matter does therefore not necessarily constitute a systemic trend towards life in our Universe. However, its sluggish reactivity at low temperatures is likely to have allowed the delivery of volatile elements essential for life at the surface of planets like the Earth. Kinetic selection may also have played a role for sorting specific active species or complex catalytic processes during the self-organization preceding life owing to the kinetic barriers hindering the reactions of covalent bonds and holding the system in a far-from-equilibrium state. As a result of both processes, early environments on telluric planets that exhibit other essential factors, namely, liquid water and light as an energy source, may then become favourable to the origin of life. In both processes, reactivity matters as much, if not more, than structures. Next to focusing on the synthesis of building blocks, emphasis must be placed on reactivity for identifying networks involving autocatalysis, replication, or positive feedback.
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