GENOMIC TECHNIQUES FOR IDENTIFICATION OF LEPTOSPIRA STRAINS

Within the Leptospiraceae family, the genus Leptospira is divided into the pathogenic L. interrogans sensu late and the saprophytic L. bifle xa sensu late. Based on DNA-DNA hybridization, L. interrogans sensu la te has been shown to contain 7 different genomic species. Each genomic species contains numerous serovars. Pulsed-field genetic studies perf ormed during this work demonstrated a great heterogeneity of serovars, within genomic species, based on restriction length polymorphism anal ysis. In contrast, an identified serovar, despite the time and region of isolation, has been shown to be highly stable in its genomic struct ure. The most likely reasons for this finding include the long generat ion time of these bacteria and the lack of acquisition of heterologous DNA. New identification techniques, based on gene amplification, have been used for Leptospira strains. These techniques represent the firs t available to facilitate the study of the epidemiology of Leptospiva.