[Relation between colony shape and the antigenic, immunogenic and virulent properties of L. interrogans]

Altogether 89 Leptospira strains isolated from humans and various animal species in different regions of the USSR, as well as in other countries, and belonging to 42 serovars and 10 serological groups were studied. The growth time and yield of the cultures on 12 solid culture media were established; these criteria were used to determine the optimum solid culture medium. The dynamic study of the changes in the colonies, connected with their age, and the parameters of the colonies, typical of L. interrogans, were determined. The cloning of Leptospira was carried out, and the biological properties of the clones thus obtained, as well as those of the original culture, were compared. In this study the form of the colonies was found to depend on the antigenic, immunogenic and virulent activity of Leptospira.