SURFACE EXCLUSION SYSTEMS OF F-LIKE PLASMIDS OF ESCHERICHIA-COLI AND THEIR GENETIC-CONTROL

Surface exclusion of plasmid F and of F-like plasmids is controlled by traS and traT genes [5, 7, 9, 11]. The problem of the distribution of the different types of surface exclusion systems (Sfx systems) determined by these genes and of their location in the genome of different plasmids remains unsolved. The aim of the investigation was to identify Sfx systems determined by genes of F-like plasmids in cells of natural strains of E. coli, to study their specificity, and to determine the possible localization of these genes in genomes of individual plasmids.