[Change in the protective activity of the ribosomal fractions of Salmonella typhimurium in mutations in the rfa region and the transduction replacement of the rfb region]. / Izmenenie protektivnoi aktivnosti ribosomal'nykh fraktsii Salmonella typhimurium pri mutatsiiakh v oblasti rfa i transduktsionnom zameshchenii oblasti rfb.

It was shown that mutation in the rfa region causing disturbances in the structure of the basal part of the polysaccharide of the cell wall or the absence of O-specific side chains led to the loss of protective activity of the ribosomal fractions isolated from the cells of the murine typhoid salmonella by sedimentation with dihydrostreptomycine sulphate. Ribosomal fractions isolated from the murine typhoid salmonella transductants with the replaced rfb region failed to protect the animals from the infection with the virulent. S. typhimurium, S. enteritidis cultures. The virulence of the mutants and transductants was also changed in comparison with the initial strains.