[Immunochemical study of meningococcal proteins].

The peptide composition and the molecular weight of peptides were determined in meningococci of serogroup A (7 strains), serogroup B (7 strains; of these, 4 strains belonged to serotype 2), serogroup C (4 strains) and serogroups D, X. Y and Z (1 strain each) by means of electrophoresis in polyacrylamide gel with sodium dodecyl sulfate. All serogroup A strains were found to contain 2 main peptides with molecular weights of 39,000 and 45,000 daltons; molecular weights of peptides in other serogroups varied in different strains. In group B and C meningococci, besides the reference strains of serotype 2, 4 more strains with peptide characteristics allowing to consider these strains belonging to serotype 2 were detected. The serotype-specific high-molecular protein preparation, purified to a considerable extent from lipopolysaccharide and hydrocarbons, was obtained from serogroup B strain, serotype 2. This preparation, when used for the immunization of rabbits, induced the formation of serotype-specific antibodies. The high-molecular protein preparation, serotype 2, was found to contain 5 individual antigenic components.