The structural proteins of Mengo virus variants

Abstract

Sodium dodecyl sulfate (SDS)-acrylamide gel electrophoresis of the solubilized proteins from purified, radioactively labeled virions of three variants of Mengo virus (L-, M-, and S-Mengo) revealed that each contains three major structural polypeptide components. These components, designated I, II, and III, are present in the same relative molecular ratios in all three variants. M-Mengo also contains a minor structural component (IV) which was not detected in any preparations of S- or L-Mengo virions. Molecular weights of the viral polypeptides, estimated from their rates of migration in SDS-acrylamide gels relative to those of known marker proteins, were found to be 31,000, 28,000, and 20,000 for major components I, II, and III, respectively, and 10,000 for minor component IV of M-Mengo. Immunological studies employing Mengo antisera in double gel-diffusion plates revealed that the three major components (but not the minor component of M-Mengo) retained their immunological reactivity and formed precipitin bands characteristic of immunological identity. These data suggest that the major structural polypeptides are immunologically identical and that all three components contribute to the antigenic composition of the virion. © 1970.