[Biological properties of bacteria of the species Shigella flexneri].

Some biological properties of S. flexneri have been studied. The strains of this bacterial species have been shown to produce DNAase in 98.8 +/- 0.77% of cases and RNAase in 97.4 +/- 1.5% of cases. The capacity for the positive reaction with Congo red as early as after 24-hour incubation in the thermostat has proved to be characteristic of S. flexneri (91.1 +/- 3.6%). If stored at 4 degrees C in semiliquid agar, S. flexneri cultures have been found to retain their capacity for producing the above-mentioned enzymes as long as 10-13 years. All S. flexneri serovars under study, with the exception of serovar 6, have shown high activity in the manifestation of their properties.