FIG. 1.

Mapping of SAPA B-cell epitopes through SPOT peptides. (A) Filters containing 12 overlapping hexapeptides synthesized in a defined array (enclosed box) were probed with sera from infected (1:100 dilution) or immunized (1:200) animals and humans. Peptides that gave positive reactions are indicated below the corresponding filter, and the consensus sequences of the defined epitopes are underlined. (B) Series of alanine or glycine-substituted analogs synthesized on the basis of the parent peptide shown above each panel were probed with the indicated serum and processed as described above. Critical residues for antibody recognition, as judged by peptide reactivity, are indicated by uppercase letters below each panel.