Interaction of RNA-containing bacteriophages with host cell: MS2-induced mutants of E. coli and the occurrence of DNA-containing derivatives of the bacteriophage MS2

Abstract

Sensitive cells of Escherichia coli AB 259 Hfr 3000 infected with RNA-containing phage MS2 produce phage particles and simultaneously continue to divide, thereby segregating sensitive cells capable of sustaining new cycles of infection. Multiplication of phage in sensitive cells gives rise to phage-resistant forms in the progeny of these cells. It is shown that this phenomenon is due not to selection of pre-existing phage-resistant mutants, but is instead the result of interaction between the phage and the cell. Unlike ordinary spontaneous or chemically induced E. coli mutants, MS2-induced phage-resistant cells are genetically unstable forms. In the course of reproduction they segregate new MS2-resistant forms with more highly expressed variations in the region encoded by the sex factors. Cells of the two final forms of MS2-induced mutants also produce a new type of phage. This new type constitutes DNA-containing forms which, however, are neutralized by anti-MS2serum. The segregation of these forms serves to confirm that the genetic substance of the RNA-containing bacteriophage is capable of being expressed as a component of the DNA-containing structure.

Sequential Combined Effect of Phages and Antibiotics on the Inactivation of Escherichia coli

“…Currently, the potential use of phage therapy in agriculture, veterinary biocontrol, food safety and in clinical treatment of human infections is also being studied [18,19,20,21,22,23,24,25,26]. A few studies have demonstrated that phages can be used to successfully prevent or control E. coli , even antibiotic resistant strains [27,28,29] and, to the best of our knowledge, only one study (from our group) have been done using the combination of phages and antibiotics to prevent the emergence of phage-resistant E. coli mutants [30].…”

A modified MS2 bacteriophage plaque reduction assay for the rapid screening of antiviral plant extracts

“…It has been demonstrated that MS2 phage uptake into E. coli cells is mediated through binding to the F pilin protein in the F pili. [ 19 ] Only F+ (but not F-) E. coli cells can take up MS2 bacteriophage, resulting in lysis. Indeed, F- E. coli cells were used in our studies as a negative control.…”

“…F+plasmids can be easily transferred from E. coli cell to E. coli cell by conjugation. [ 19 ] It is also likely that a similar exchange is possible between different bacterial species. It is therefore surprising that there are no other reports of MS2 plaque formation in other bacterial species.…”