The COFRADIC or 'COmbined FRActional DIagonal Chromatography' technology specifically isolates peptides holding the amino terminal part of proteins. Since protein processing gives rise to a new protein fragment, isolation of N-terminal peptides points to proteolytic event and permit analysis of protein processing on a proteome-wide scale. The proteome-wide degradomics methods will be applied to study granzyme-mediated target and host-virus interactions.