Insoluble elastin was used as a substrate to characterize the peptide bond specificities of
human (HME) and mouse macrophage elastase (MME) and to compare these enzymes with
other mammalian metalloproteinases and serine elastases. New amino termini detected by
protein sequence analysis in insoluble elastin following proteolytic digestion reveal the P′
1 residues in the carboxyl-terminal direction from the scissile bond. The relative proportion of
each amino acid in this position reflects the proteolytic preference of the elastolytic enzyme …