FIG. 1.

(A) Schematic diagram of CNF1 truncated toxins, with the regions and epitopes recognized by several CNF MAbs indicated at the top. MAbs JC4 and NG8 can neutralize only CNF1, while MAb BF8 can neutralize both CNF1 and CNF2. aa, amino acids. (B) Western blots of purified wild-type and truncated CNF1 toxins. Toxins (2 μg of CNF2 and the CNF1 truncated toxins and 500 ng of CNF1) were applied to SDS-PAGE gels and transferred to nitrocellulose membranes. Blots were probed with anti-CNF1 polyclonal antisera, followed by an HRP-conjugated secondary antibody and the ECL substrate. Circles indicate the position of each full-length toxin.