[The application of the crossed immunoelectrophoresis to strains of the genus bacillus may be useful for diagnostic and taxonomic purposes (author's transl)].

The two-dimensional immunoelectrophoresis was used in an attempt to differentiate between the species of the genus Bacillus and reveal their taxonomic relationship. Three strains each of the species B. subtilis, B. licheniformis, B. cereus and one strain each of the species B. laterosporus and B. sphaericus were selected. The substrate investigated was ultrasonic extract. The evaluation of the immunoelectropherogrames was based on the numbers of the precipitates as well as on the arrangement and shape of the precipitation lines. In most cases it was possible to identify the strains belonging to a certain species because of the fact, that in the homologeous system considerable more precipitates occurred than in heterologeous systems and in addition the optical pattern of the precipitation showed up with species-specific characteristics. The extent of the divergence between the homologic and a given heterologic pattern mirrored frequently the degree of affinity of the strain involved.