Poster Presentation 8th Modern Solid Phase Peptide Synthesis & Its Applications Symposium 2022

Expanding the versatility and scope of the oxime ligation (#130)

Anke Hering 1 , Nayara Braga Emidio 1 , Markus Muttenthaler 1 2
  1. Institute for Molecular Bioscience, The University of Queensland, Brisbane, Qld, Australia
  2. Faculty of Chemistry, Institute of Biological Chemistry, University of Vienna, Vienna, Austria

The oxime ligation is a valuable bioorthogonal reaction used to modify peptides and proteins. The synthesis, manipulation and storage of disulfide-rich aminooxy-peptides is however challenging due to the aminooxy group's high reactivity, restricting its use to linear peptides and N-terminal modifications. This is a substantial limitation considering the significance of disulfide-rich peptides and proteins in health and disease. Here, we overcome these limitations through a synthetic strategy enabling regiospecific incorporation of the aminooxy group within peptides, oxidative folding and production of stable aminooxy precursors for long-term storage. We further developed a one-pot protocol enabling complete ligation within 5 min, a considerable improvement to the standard multi-hour protocols. The latter is particularly important for radiochemistry applications due to the short half-lives of many radionuclides, and we applied our protocol to the rapid preparation of PET tracers. These new strategies and protocols support several new ligand design strategies and research avenues for the study and application of disulfide-rich peptides and proteins.