Figure 4

Detection of multiple ADP-ribosylarginines by two-dimensional (2-D) electrophoresis. The amino acids sequences of CTc fused with outer membrane signal peptide was shown in (A). CTc was incubated with or without 250 μM NAD⁺(B). CTc incubated with or without NAD⁺ was further digested with LysC prior to peptide 2-D electrophoresis (D). Amino acid sequences of three major predicted proteolytic products are shown in (C). Circle I indicates the partially digested peptide 489–616. Circle II indicates spots shifted from the auto-ADP-ribosylated peptide 509–616. Spots A and B are peptides 509–616 and 423–488, respectively.