Fig. 4.

Location of the epitope to antibody A12 on the surface of poliovirus. (A) Scheme of poliovirus capsid showing the location of a single capsomer relative to the 5-, 3-, and 2-fold axes of symmetry. Canyon surrounds the 5-fold axis. VP1, VP2, and VP3 proteins are shown. (B) Three-dimensional structure of poliovirus capsomer. Color codes for proteins VP1, VP2, and VP3 are the same as in panel A. Antigenic sites 1 and 2 are shown in red and orange, respectively, and amino acids replaced in escape mutants are shown in black.