title: Formation of activated biomolecules by condensation on mineral surfaces--a comparison of peptide bond formation and phosphate condensation.
abstract: Many studies have reported condensation reactions of prebiotic molecules, such as the formation of peptide bonds between amino acids, to occur to some degree on mineral surfaces. We have studied several such reactions on the same divided silica. When drying steps are applied, the equilibria of peptide formation from glycine, and polyphosphate formation from monophosphate, are displaced to the right because these reactions are dehydrating condensations, accompanied by the emission of water. In contrast, the equilibrium of AMP dismutation is not significantly favored by drying. The silica surface plays little role (if any) in the thermochemistry of the condensation reactions, but is does play a significant kinetic role by acting as a catalyst, lowering the condensation temperatures with respect to bulk solids. Of course, the surface also catalyzes the inverse hydrolysis reactions.
authors.affiliation: Laboratoire de Réactivité de Surface (UMR 7197 CNRS), UPMC Univ Paris 06, Case courrier 178, 3 Rue Galilée, Ivry-sur-Seine, 94200, Paris, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Georgelin
authors.forename: Maguy
authors.initials: M
authors.lastname: Jaber
authors.forename: Houssein
authors.initials: H
authors.lastname: Bazzi
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Lambert
mesh_terms: D019418:Evolution, Chemical; D005998:Glycine / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008903:Minerals / Q000737:chemistry; D000069497:Origin of Life; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry; D010710:Phosphates / Q000138:chemical synthesis* / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013499:Surface Properties; D013818:Thermogravimetry
chemical_list: D008903:Minerals; D010455:Peptides; D010710:Phosphates; D012822:Silicon Dioxide; D005998:Glycine