Figure 3.
Summary of NEM modifications in each of the HPLC peaks. Vertical red lines indicate trypsin cleavage sites and Cys residues with a blue background identify NEM modifications. Peak b contains two modifications thus identifying the Cys111-Cys132 disulfide. Peak c contains two additional modifications demonstrating linkage between Cys116-Cys123, and so forth. The resulting disulfide linkage map is shown below the sequences. The thin lines are consistent with disulfides identified in the NMR structure; the thick lines are newly identified by chemical mapping here.