Abstract: Hydrogen-Deuterium Exchange and Fragmentation Studies of Peptides and Amino Acids

Mass spectrometry-based proteomics experiments, are broadly related to automated peptide sequencing. Mass spectrometry experimentation provides structure elucidation and give a relative understanding of gas-phase properties, fragmentation, and interactions between amino acid side groups, which are often neglected in automated peptide sequencing algorithms. This summer, I will performing H/D exchange on various amino acids and peptide of interest to the Poutsma’s lab, such as lysine, cysteine and serine. H/D  exchange will be performed in a quadrupole ion trap instrument.  Peptide precursor ions are generated by ESI, isolated, and allowed to react with D2O at low pressure for varying reaction times.  HDX experiments were also performed on peptide fragment ions generated by CID, which are re-isolated in MS3 mode and then allowed to react with D2O. Experiment results will contribute to the understanding and refinement these rules in order to allow for improved peptide identification.