title: Ester-Mediated Amide Bond Formation Driven by Wet-Dry Cycles: A Possible Path to Polypeptides on the Prebiotic Earth.
abstract: Although it is generally accepted that amino acids were present on the prebiotic Earth, the mechanism by which α-amino acids were condensed into polypeptides before the emergence of enzymes remains unsolved. Here, we demonstrate a prebiotically plausible mechanism for peptide (amide) bond formation that is enabled by α-hydroxy acids, which were likely present along with amino acids on the early Earth. Together, α-hydroxy acids and α-amino acids form depsipeptides-oligomers with a combination of ester and amide linkages-in model prebiotic reactions that are driven by wet-cool/dry-hot cycles. Through a combination of ester-amide bond exchange and ester bond hydrolysis, depsipeptides are enriched with amino acids over time. These results support a long-standing hypothesis that peptides might have arisen from ester-based precursors.
authors.affiliation: NSF/NASA Center for Chemical Evolution (USA).|School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA (USA).
authors.forename: Jay G
authors.initials: JG
authors.lastname: Forsythe
authors.affiliation: NSF/NASA Center for Chemical Evolution (USA).|School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA (USA).
authors.forename: Sheng-Sheng
authors.initials: SS
authors.lastname: Yu
authors.affiliation: NSF/NASA Center for Chemical Evolution (USA).|School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA (USA).
authors.forename: Irena
authors.initials: I
authors.lastname: Mamajanov
authors.affiliation: NSF/NASA Center for Chemical Evolution (USA).|School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA (USA).
authors.forename: Martha A
authors.initials: MA
authors.lastname: Grover
authors.affiliation: NSF/NASA Center for Chemical Evolution (USA). rkrishna@scripps.edu.|Department of Chemistry, The Scripps Research Institute, La Jolla, CA (USA). rkrishna@scripps.edu.
authors.forename: Ramanarayanan
authors.initials: R
authors.lastname: Krishnamurthy
authors.affiliation: NSF/NASA Center for Chemical Evolution (USA). facundo.fernandez@chemistry.gatech.edu.|School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA (USA). facundo.fernandez@chemistry.gatech.edu.
authors.forename: Facundo M
authors.initials: FM
authors.lastname: Fernández
authors.affiliation: NSF/NASA Center for Chemical Evolution (USA). hud@gatech.edu.|School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA (USA). hud@gatech.edu.
authors.forename: Nicholas V
authors.initials: NV
authors.lastname: Hud
mesh_terms: D000577:Amides / Q000737:chemistry*; D018534:Earth, Planet; D004952:Esters / Q000737:chemistry*; D019418:Evolution, Chemical; D000069497:Origin of Life; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000737:chemistry*; D017155:Wettability
chemical_list: D000577:Amides; D004952:Esters; D010455:Peptides; D014867:Water
keywords: chemical evolution; day-night cycle; depsipeptides; origins-of-life; proto-peptides