[The description of an esculin-positive biovar of Pseudomonas aeruginosa].

In the study of 280 P. aeruginosa strains isolated in different hospitals of St. Petersburg for the first time 48 strains capable of hydrolyzing esculin have been detected. The hydrolysis of esculin is determined in plates with the use of the microvolume techniques the results were evaluated after 3-hour incubation at 37 degrees C. The data confirming the existence of the exculin-positive biovar of P. aeruginosa have been obtained; these data show the wide spread of esculin-positive strains in hospitals of different specialization (17.1 +/- 5.1% of P. aeruginosa strains), the characteristic combination of the sign of esculin hydrolysis with such signs as the absence of the smell of trimethylamine and the phenomenon of "iridescent lysis" of the colonies, the stability of the sign of esculin hydrolysis in strains, repeatedly isolated from patients, after the storage of the cultures and their treatment with plasmid-eliminating preparation. The name "esculinolytica" has been proposed for this biovar. The typing strain of biovar esculinolytica has been deposited in the culture collection of the Russian Research Institute of Agricultural Microbiology as P. aeruginosa ARRIAM 64-A. This biovar been found to be most widely spread in urological hospitals, where esculin-positive strains are isolated 3 times more frequently (32.2 +/- 5.1% of P. aeruginosa strains) than in surgical hospitals (10.7 +/- 2.2%).