FOOT-AND-MOUTH-DISEASE VIRUS IMMUNOGENIC CAPSID PROTEIN VPT - N-TERMINAL SEQUENCES AND IMMUNOGENIC PEPTIDES OBTAINED BY CNBR AND TRYPTIC CLEAVAGES

The immunogenic capsid protein (VPT), circa 30 kilodaltons (kd), of foot-and-mouth disease virus was examined for (i) its ability to induce neutralizing antibody in guinea pigs after chemical modifications and CNBr or tryptic cleavages and (ii) N-terminal amino acid sequence homology across three virus types. The immunogenicity of VPT was inactivated by glutaraldehyde treatment, carboxymethylation and maleylation or citraconylation. However, de-citraconylation restored part of the lost activity. Cleavage of type A12 VPT with CNBr produced an immunogenic peptide of circa 13 kd. A slightly larger (ca. 16 kd) immunogenic doublet, VPTab, was obtained by tryptic cleavage of VPT in the virion. Sequence homologies of circa 85% were found between the first 26 amino acids at the N-terminus of VP chains from virus types A12 strain 119 (A12), C3 Resende (C3R) and O1 Brugge (O1B). © 1979 S. Karger AG, Basel.