[Behavior of the F-like plasmids in bacterial cells with a varying capacity genetic recombination].

F-like plasmids (FBl, FBl drd, F-lac+) were transferred to the recipient strains E. coli, K-12 with different recombination ability. Then the sensitivity of these strains to ultra-violet irradiation and also the stability of the mentioned plasmids under conditions of bacteria treatment with elimination agents was determined. The presence of any F-like plasmids under study failed to influence the ultra-violet sensitivity of the bacterial cells. On the other hand, the research results of spontaneous and inducec elimination of these plasmids indicated considerable differences in relation to the elimination agents. It is supposed that the stability of individual F-like plasmids in the cells largely depended on the genetic differences in rec A gene in the bacterial cells containing them.