[Relation between the Yersinia phage and bacteriophages isolated from the environment]

The bacteriophage designated RD2 has been isolated from the sewage in Rostov-on-Don city and studied. The morphology of bacteriophage particles and the biological properties of the bacteriophage make it related to the plague bacteriophage isolated by D'Errel. The molecular masses of the compared bacteriophages are almost identical being 26.4 +/- 0.4 Md for RD2 and 24.7 +/- 0.2 Md for D'Errel bacteriophage. The DNAs of the bacteriophages share 80% of homology and possess 15 nonhomologous regions scattered along the genomes. The phages are serologically related. The DNAs of both bacteriophages give the similar pattern of hydrolysis by restriction endonuclease EcoRV, but have the different sensitivity to many other restriction endonucleases. The protein specter of bacteriophage RD2 contains 18 polypeptides (11 minor ones), while the one of D'Errel bacteriophage contains 7 polypeptides similar in molecular mass with the polypeptides of RD2. The bacteriophage RD2 cannot be considered one of the plague causative agents of bacteriophages since the region where it has been isolated has a long epidemiological and epizootical record of absence of plague.