Figure 7

Intramolecular crosslinking peptide. (A) MALDI-TOF profile of the tryptic digest of dimeric band of IN 1–105 crosslinked with BS3. Samples were digested overnight at 37°C with trypsin in a ratio of 1:20 wt/wt (enzyme: protein). The image showed the peak 4999.5366 (m/z) corresponding at the intermolecular peptide 25–33 and 1–31 with K31 and K20 or K24 modified. (B) LC-MS/MS profile of the chymotryptic IN 1–105 were cross-linked with BS3. Samples were digested overnight at 37°C with chymotrypsin in a ratio of 1:20 wt/wt (enzyme:protein). The image shows the ionization and sequence of the LC peak (indicated in the inset) corresponding at the intermolecular peptide 15–25 and 30–35 with K31 and K20 crosslinked.