[Inhibitor production, a stable feature of plague pathogen].

Application of the methods developed by the author to the plague causative agent isolated in six natural plague foci provided detection of its ability to synthesize a factor inhibiting the growth of the producing strain and cultures isolated from the same focus. In the strains isolated from these foci the inhibitor presence was stable on the agar consisting of fermentative casein hydrolysate and 0.6 per cent of lithium chloride when the indicator strains were incubated under definite temperature conditions. The results of the present study and previous studies of the author, as well as the literature data suggested that the ability to synthesize the inhibitor is a stable feature of the plague causative agent.