[Characteristics of the protease activity of Vibrio cholerae strains and mutants with various biological properties].

The study of 65 V. cholerae strains and mutants revealed that protease activity was high in choleragenic strains and mostly low, sometimes even not manifested, in noncholeragenic strains. The use of inhibitors made it possible to determine three types of protease.

[Potentials and conditions for the reversion of pathogenic properties of the causative agent of cholera in an experiment].

The passage of V. cholerae noncholerigenic strains and their mutants, both in vitro and in vivo, has demonstrated that strains in which one of such properties as mobility, viability, adhesive, lecithinase and neuraminidase activities, is sharply decreased or lost, are still capable of reversion to cholerigenic forms. V.

[Assessment of the importance of certain properties for the virulence of Vibrio cholerae and the detection of their correlations].

The study of 65 V. cholerae strains and mutants with different biological characteristics has revealed that their virulence directly correlates with their sensitivity to diagnostic cholera phages, lecithnase activity, viability and inversely correlates with their hemolytic activity. The role of lecithinase activity in a number of properties linked with cholerigenicity has been shown.