TY - JOUR
T1 - Quantifying the extent of amide and peptide bond synthesis across conditions relevant to geologic and planetary environments
AU - Robinson, Kirtland J.
AU - Bockisch, Christiana
AU - Gould, Ian R.
AU - Liao, Yiju
AU - Yang, Ziming
AU - Glein, Christopher R.
AU - Shaver, Garrett D.
AU - Hartnett, Hilairy E.
AU - Williams, Lynda B.
AU - Shock, Everett L.
N1 - Funding Information:
This work was supported by NASA Habitable Worlds Grant NNX16AO82G and NASA Astrobiology Program Award 80NSSC19K1427. Z.Y. and Y.L. acknowledge support from the Michigan Space Grant Consortium and Oakland University. C.R.G. was partly supported by the NASA Astrobiology Institute through its JPL-led team entitled Habitability of Hydrocarbon Worlds: Titan and Beyond. K.J.R. was partly supported by an appointment to the NASA Postdoctoral Program at Woods Hole Oceanographic Institution, administered by Universities Space Research Association under contract with NASA. K.J.R. and E.L.S. acknowledge support from NASA Grant 80NSSC19K1427. E.L.S., I.R.G, G.D.S, and K.J.R. acknowledge support from NASA Grant 80NSSC20K1408.
Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2021/5/1
Y1 - 2021/5/1
N2 - Amide bonds are fundamental products in biochemistry, forming peptides critical to protein formation, but amide bonds are also detected in sterile environments and abiotic synthesis experiments. The abiotic formation of amide bonds may represent a prerequisite to the origin of life. Here we report thermodynamic models that predict optimal conditions for amide bond synthesis across geologically relevant ranges of temperature, pressure, and pH. We modeled acetamide formation from acetic acid and ammonia as a simple analog to peptide bond formation, and tested this model with hydrothermal experiments examining analogous reactions of amides including benzanilide and related structures. We also expanded predictions for optimizing diglycine formation, revealing that in addition to synthesis becoming more favorable at near-ambient pressures (Psat) with increasing temperatures, the strongest thermodynamic drive exists at extremely high pressures (>15,000 bar) and decreasing temperatures. Beyond implications for life's origins, the reactants and products involved in simple amide formation reactions can potentially be used as geochemical tracers for planetary exploration of environments that may be habitable.
AB - Amide bonds are fundamental products in biochemistry, forming peptides critical to protein formation, but amide bonds are also detected in sterile environments and abiotic synthesis experiments. The abiotic formation of amide bonds may represent a prerequisite to the origin of life. Here we report thermodynamic models that predict optimal conditions for amide bond synthesis across geologically relevant ranges of temperature, pressure, and pH. We modeled acetamide formation from acetic acid and ammonia as a simple analog to peptide bond formation, and tested this model with hydrothermal experiments examining analogous reactions of amides including benzanilide and related structures. We also expanded predictions for optimizing diglycine formation, revealing that in addition to synthesis becoming more favorable at near-ambient pressures (Psat) with increasing temperatures, the strongest thermodynamic drive exists at extremely high pressures (>15,000 bar) and decreasing temperatures. Beyond implications for life's origins, the reactants and products involved in simple amide formation reactions can potentially be used as geochemical tracers for planetary exploration of environments that may be habitable.
KW - Enceladus
KW - Hydrothermal experiments
KW - Ocean worlds
KW - Origin of life
KW - Prebiotic
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U2 - 10.1016/j.gca.2021.01.038
DO - 10.1016/j.gca.2021.01.038
M3 - Article
AN - SCOPUS:85101886113
VL - 300
SP - 318
EP - 332
JO - Geochmica et Cosmochimica Acta
JF - Geochmica et Cosmochimica Acta
SN - 0016-7037
ER -