[Functional characteristics of plasmids of Shigella sonnei 47 strains].

The phenotypic characteristics of Shigella sonnei strain 47 containing 7 plasmids of low molecular weight and 2 plasmids 60-100 Md large have been studied. The strains of Escherichia coli containing the single plasmids or plasmid groups from Shigella sonnei have been obtained by transformation and conjugation. The comparison of phenotypes of the obtained strains has helped to find the plasmid location of the determinants for streptomycin resistance (P7), genes for colicinogenicity and colicin immunity (P5), the enzymes of host cell specificity system Sso47I (P6), Sso47II (P4), and the genes for the conjugative DNA transfer (P9). Escherichia coli strains producing individual restriction enzymes SsoI and SsoII have been isolated.