Substrate specificity profiling of human Neutrophil Elastase A.

Positional scanning of the P4 to P1 subsites of NE using the PS-SCL assay. B An iceLogo illustrating amino acids that are most frequently (above axis) and least frequently (below axis) observed in the P4 to P4′ sites of NE. Residues that are highlighted in black are significantly (p = 0.05) enriched or de-enriched in the subsites relative to the frequency that these same amino acids are found in the peptide library (5.2 +/- 0.5%). C. A representative “donor signature” consisting of 40 cleavage sites that are common to the three donors. D. A pie chart representing the 40 cleavage sites that are common to the donor samples. 33 of these sites are also hydrolyzed by NE.