title: Energy flows, metabolism and translation.
abstract: Thermodynamics provides an essential approach to understanding how living organisms survive in an organized state despite the second law. Exchanges with the environment constantly produce large amounts of entropy compensating for their own organized state. In addition to this constraint on self-organization, the free energy delivered to the system, in terms of potential, is essential to understand how a complex chemistry based on carbon has emerged. Accordingly, the amount of free energy brought about through discrete events must reach the strength needed to induce chemical changes in which covalent bonds are reorganized. The consequence of this constraint was scrutinized in relation to both the development of a carbon metabolism and that of translation. Amino acyl adenylates involved as aminoacylation intermediates of the latter process reach one of the higher free energy levels found in biochemistry, which may be informative on the range in which energy was exchanged in essential early biochemical processes. The consistency of this range with the amount of energy needed to weaken covalent bonds involving carbon may not be accidental but the consequence of the above mentioned thermodynamic constraints. This could be useful in building scenarios for the emergence and early development of translation.
authors.affiliation: Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, Université Montpellier 1 and 2, 34095 Montpellier Cedex 5, France. rpascal@univ-montp2.fr
authors.forename: Robert
authors.initials: R
authors.lastname: Pascal
authors.forename: Laurent
authors.initials: L
authors.lastname: Boiteau
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D049148:Aminoacylation; D005075:Biological Evolution; D002244:Carbon / Q000378:metabolism; D018534:Earth, Planet; D004734:Energy Metabolism; D005557:Formaldehyde / Q000378:metabolism; D052836:Heterotrophic Processes; D009711:Nucleotides / Q000378:metabolism; D000069497:Origin of Life; D010455:Peptides / Q000378:metabolism; D010766:Phosphorylation; D014176:Protein Biosynthesis; D018892:Proton-Motive Force; D013816:Thermodynamics
chemical_list: D009711:Nucleotides; D010455:Peptides; D005557:Formaldehyde; D002244:Carbon; D000255:Adenosine Triphosphate