Figure 1: SDS-PAGE analysis of purified recombinant CTB-Sm14 and its ability to fold into pentameric/oligomeric structures. Lane 1. Molecular Mass Marker. Lane 2. rCTB-Sm14 in the presence of β-mercapthoethanol and heated at 96oC. Lane 3. rCTB-Sm14 in non-reducing conditions and not heated.