Determination of proteolytic signature of PR3, CG and NSP4.
A-C. IceLogos representing the P4 to P4′ sites for PR3, CG and NSP4. Amino acids that are most frequently observed (above axis) and least frequently observed (below axis) are illustrated. The number of cleavage sites used to make each iceLogo are listed in the bottom right-hand corner. Residues that are highlighted in black text are significantly (p ≤ 0.05) enriched relative to the frequency that these same amino acids are found in the peptide library (5.2 +/- 0.5%). The amino acid ‘n’ corresponds to norleucine. D. A 4-way venn diagram illustrating the number of unique and overlapping peptide bonds that are cleaved by each neutrophil serine protease. E. A pie chart representing the 40 cleavage sites that are common to the donor samples. ‘Shared’ corresponds to cleavage sites that are derived from more than one neutrophil serine protease.