title: Aqueous synthesis of peptide thioesters from amino acids and a thiol using 1,1'-carbonyldiimidazole.
abstract: A new method was developed for the synthesis of peptide thioesters from free amino acids and thiols in water. This one-pot simple method involves two steps: (1) activation in water of an amino acid presumably as its N-carboxyanhydride (NCA) using 1,1'-carbonyldiimidazole (CDI), and (2) subsequent condensation of the activated amino acid-NCA in the presence of a thiol. With this method citrulline peptide thioesters containing up to 10 amino acid residues were prepared in a single reaction. This aqueous synthetic method provides a simple way to prepare peptide thioesters for studies of peptide replication involving ligation of peptide thioesters on peptide templates. The relevance of peptide replication to the origin-of-life process is supported by previous studies showing that amino acid thioesters (peptide thioester precursors) can be synthesized under prebiotic conditions by reaction of small sugars with ammonia and a thiol.
authors.affiliation: SETI Institute, Mail Stop 239-4, NASA Ames Research Center, Moffett Field, CA, 94035-1000, U.S.A. aweber@mail.arc.nasa.gov
authors.forename: Arthur L
authors.initials: AL
authors.lastname: Weber
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004952:Esters / Q000138:chemical synthesis; D019418:Evolution, Chemical; D007093:Imidazoles / Q000737:chemistry*; D000069497:Origin of Life; D010455:Peptides / Q000138:chemical synthesis*; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis*; D014867:Water / Q000737:chemistry
chemical_list: D000596:Amino Acids; D004952:Esters; D007093:Imidazoles; D010455:Peptides; D013438:Sulfhydryl Compounds; D014867:Water; C006900:N,N-carbonyldiimidazole