Antigenic differences between infective and noninfective strains of Rhizobium trifolii

Immunodiffusion and immunoelectrophoresis techniques have revealed the presence of soluble antigens in sonicated preparations of four infective strains of Rhizobium trifolii which were absent in similar preparations of related noninfective mutants derived from the infective strains. The soluble antigens unique to the infective strains were cross-reactive with one another.