TY - JOUR
T1 - The potential for abiotic organic synthesis and biosynthesis at seafloor hydrothermal systems
AU - Shock, Everett
AU - Canovas, P.
N1 - Copyright:
Copyright 2010 Elsevier B.V., All rights reserved.
PY - 2010/5
Y1 - 2010/5
N2 - Geofluids (2010) 10, 161-192. Calculations are presented of the extent to which chemical disequilibria are generated when submarine hydrothermal fluids mix with sea water. These calculations involve quantifying the chemical affinity for individual reactions by comparing equilibrium compositions with the compositions of mixtures in which oxidation-reduction reactions are inhibited. The oxidation-reduction reactions that depart from equilibrium in these systems provide energy for chemotrophic microbial metabolism. Methanogenesis is an example of this phenomenon, in which the combination of carbon dioxide, hydrogen and methane induced by fluid mixing is far from equilibrium, which can be approached if more methane is generated. Similarly, the production of other organic compounds is also favorable under the same conditions that permit methanogenesis. Alkanes, alkenes, alcohols, aldehydes, carboxylic acids and amino acids are among the compounds that, if formed, would lower the energetic state of the chemical composition generated in mixed fluids. The resulting positive values of chemical affinity correspond to the thermodynamic drive required for abiotic organic synthesis. It is also possible that energy release accompanies biosynthesis by chemotrophic organisms. In this way, hydrothermal ecosystems differ radically from familiar ecosystems at Earth's surface. If captured, the energy released may be sufficient to drive biosynthesis of carbohydrates, purines, pyrimidines and other compounds which require energy inputs.
AB - Geofluids (2010) 10, 161-192. Calculations are presented of the extent to which chemical disequilibria are generated when submarine hydrothermal fluids mix with sea water. These calculations involve quantifying the chemical affinity for individual reactions by comparing equilibrium compositions with the compositions of mixtures in which oxidation-reduction reactions are inhibited. The oxidation-reduction reactions that depart from equilibrium in these systems provide energy for chemotrophic microbial metabolism. Methanogenesis is an example of this phenomenon, in which the combination of carbon dioxide, hydrogen and methane induced by fluid mixing is far from equilibrium, which can be approached if more methane is generated. Similarly, the production of other organic compounds is also favorable under the same conditions that permit methanogenesis. Alkanes, alkenes, alcohols, aldehydes, carboxylic acids and amino acids are among the compounds that, if formed, would lower the energetic state of the chemical composition generated in mixed fluids. The resulting positive values of chemical affinity correspond to the thermodynamic drive required for abiotic organic synthesis. It is also possible that energy release accompanies biosynthesis by chemotrophic organisms. In this way, hydrothermal ecosystems differ radically from familiar ecosystems at Earth's surface. If captured, the energy released may be sufficient to drive biosynthesis of carbohydrates, purines, pyrimidines and other compounds which require energy inputs.
KW - Abiotic organic synthesis
KW - Affinity
KW - Amino acids
KW - Biosynthesis
KW - Carbohydrates
KW - Hydrothermal
KW - Organic acids
KW - Seafloor hydrothermal systems
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U2 - 10.1111/j.1468-8123.2010.00277.x
DO - 10.1111/j.1468-8123.2010.00277.x
M3 - Article
AN - SCOPUS:77953772201
SN - 1468-8115
VL - 10
SP - 161
EP - 192
JO - Geofluids
JF - Geofluids
IS - 1-2
ER -