[Transmission of plasmid Rldrd19 from E. coli to Hafnia]

Investigations carried out demonstrated a possibility of transmission of plasmid Rldrd19 from E. coli to Hafnia. The incidence of the plasmid transmission varied from 10(-7) to 10(-9) and depended on the properfies of Hafnia strains. Tra-operon of plasmid Rldrd19 in the Hafnia 614 strain functioned with the same efficacy as in E. coli. Plasmid Rldrd19 in Hafnia was unstable and was eliminated from the cells in case of storage at low temperatures. As shown, plasmid Rldrd19 was under strict replication control in Hafnia as in E. coli. Formation of the CCC-form of the plasmid Rldrd19 was suppressed in Hafnia at 29--30 degrees C and was not suppressed in E. coli.