Structural, biochemical and electrostatic basis of serotype specificity in bovine enteroviruses

We have performed immunostructural analyses of three closely related picornaviruses in order to gain understanding of the biochemical and structural basis of serotype specificity. We carried out sequence alignments of the capsid regions of three bovine enterovirus strains: VG-5-27 and M-4 from serotype 1 and PS-87 from serotype 2. Using our knowledge of the three dimensional and antigenic structure of strain VG-5-27 and the high levels of sequence identity between the strains, we have calculated the structures and solvent-accessible electrostatic potentials of the epitopes of all three viruses. We have demonstrated the viability of the molecular models of the epitopes of the M-4 and PS-87 strains. In each of the strains, we have explained the serotype specificities in terms of specific physical and chemical properties, and identified individual residues which are pivotal in determination of antibody recognition. These changes are in agreement with the known cross-reactivity of peptide and antiviral sera, showing that it is possible to derive structures for short variable sections of proteins of high sequence identity using molecular modelling which are significant in terms of biological function. We believe this study to be a novel approach in the analysis of virus serotype specificity.