[Interrelation of the sensitivity of Salmonella derby cells to phage dp8 with the R plasmid of Salmonella derby].

In the process of studying phage--Salmonella derby plasmid interaction effect, it has been found that the absence of the plasmid blocks the adsorption step and the step of phage penetration into the cell. However, the lytic functions and those responsible in maintenance of the lysogenic state are independent of plasmid. Probably, resistance of plasmidless cells of S. derby to extracellular dp8 phage is mediated by the absence of plasmid-borne genes in S. derby coding for membrane peptides which are indispensible for adsorption and DNA penetration into the cell.