A high-throughput sequence determination for one cyclic peptide immobilized on a single bead by the one-pot cyanidation followed by MALDI-TOF–MS/MS for discovery of interacting peptides

One cyclic peptide immobilized on one gel-type bead has been employed for the discovery of both interacting peptides and/or medicinal medium-sized molecules. Although high-throughput characterization of recognized peptides has been a bottleneck, here, we describe direct liberation from beads by a one-pot reaction using 2-nitro-5-thiocyanatobenzoic acid followed by mass spectrometry to realize faster and routine sequencing of the peptide on the beads. This is useful for the investigation of protein–protein interactions as well as discovery of drug candidates.