title: The role of metal ions in chemical evolution: polymerization of alanine and glycine in a cation-exchanged clay environment.
abstract: The effect of the exchangeable cation on the condensation of glycine and alanine was investigated using a series of homoinic bentonites. A cycling procedure of drying, warming and wetting was employed. Peptide bond formation was observed, and the effectiveness of metal ions to catalyze the condensation was Cu2+ greater than Ni2+ approximately Zn2+ greater than Na+. Glycine showed 6% of the monomer incorporated into oligomers with the largest detected being the pentamer. Alanine showed less peptide bond formation (a maximum of 2%) and only the dimer was observed.
mesh_terms: D000409:Alanine; D001546:Bentonite; D002412:Cations; D003300:Copper; D005998:Glycine; D007474:Ion Exchange; D008670:Metals; D009532:Nickel; D009842:Oligopeptides; D012964:Sodium; D015032:Zinc
chemical_list: D002412:Cations; D008670:Metals; D009842:Oligopeptides; D001546:Bentonite; D003300:Copper; D009532:Nickel; D012964:Sodium; D015032:Zinc; D000409:Alanine; D005998:Glycine