Figure 1.
Immunogen design, expression, purification, and immunoblot analysis of the CTB-Fim2 fusion protein. (a) Schematic representation of immunogen design. (b) Protein expression and purification in the E. coli (SI) strain transformed with pAE-CTB-Fim2. Protein expression was assayed using a 10% SDS-PAGE gel and shows a 36 kDa band. (c) Analysis of the recombinant CTB-Fim2 protein after elution from Ni2+-charged beads with 250 mM imidazole. (d) Reactive protein bands probed with a mouse antiserum (1 : 2500) against CTB. NI and I stand for noninduced and induced bacterial extract, respectively.