Fig. S5.

Representative MS spectra of key peptic peptides after H/D exchange experiments of caspase-6 maturation variants. The relative locations of the highlighted peptic peptides for the following regions are mapped onto the hybrid model of procaspase-6: purple blue, peptide including the 26–32 region; green, top of 130s region; orange, 130s region; cyan, part of L1; red, L2. The amino acid sequence, the MS charge-state distribution, and the residue numbers covered by the representative peptic peptide are also indicated. The asterisk designates the D to A substitution at the indicated proteolytic cleavage site, rendering that site uncleavable.