Related Experiment Video
Updated: Jan 23, 2026

Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Water-assisted peptide bond formation between two double amino acid molecules in the gas phase
1Laboratory of Quantum Chemistry, Faculty of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308, Gdańsk, Poland. sylwia.freza@ug.edu.pl.
Abstract:
The gas phase mechanism of the peptide bond formation between two double amino acid (DAA) molecules described by the (NH2)2C(COOH)2 formula is investigated in the presence of a water molecule. Formations of trans and cis DAA-DAA dipeptide products along both concerted and stepwise mechanisms have been studied at the CCSD(T)/aug-cc-pVDZ//MP2/aug-cc-pVDZ level. The results indicate that the activation energy barriers estimated for the water-assisted mechanisms are significantly reduced in comparison to the corresponding uncatalyzed reactions. The trans DAA-DAA isomer is expected to dominate in the final product due to its larger stability compared to the cis DAA-DAA product.
More Related Videos
Related Concept Videos
Peptide Bonds
Amino acids
Phase II Reactions: Sulfation and Conjugation with α-Amino Acids
Bond Energies and Bond Lengths
Phase II Reactions: Glutathione Conjugation and Mercapturic Acid Formation
Several distinctive characteristics distinguish glutathione conjugation from other phase II...
Amino Acid Catabolism

