Formation of activated biomolecules by condensation on mineral surfaces--a comparison of peptide bond formation and phosphate condensation.

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.

Non-biological selectivity in amino acids polymerization on TiO₂ nanoparticles.

For the first, time a strong selectivity is evidenced in inorganic peptide synthesis. When an equimolar mixture of Ala and Arg monomers is added to the synthesis medium of TiO₂ nanoparticles from Ti(IV) isopropoxide in benzyl alcohol, the Ala-Arg dipeptide is observed by ¹³C NMR in the resulting solid, at the exclusion of other dipeptides or higher peptides.