Multilocus Sequence Analysis for Typing Leptospira interrogans and

Fifty-three strains belonging to the pathogenic species Leptospira interrogans and Leptospira kirschneri were analyzed by multilocus sequence analysis. The species formed two distinct branches. In the L. interrogans branch, the phylogenetic tree clustered the strains into three subgroups. Genogroups and serogroups were superimposed but not strictly. Leptospira spp. belong to the bacterial phylum “Spiro-chaetes. ” Members of the genus Leptospira are generally di-vided into a pathogenic species, Leptospira interrogans sensu lato, and a nonpathogenic species, Leptospira biflexa sensu lato (3, 12). Pathogenic members are the causal agents of leptospi-rosis, a widespread zoonosis that is a major public health di-lemma. In the natural reservoirs of the bacteria, such as ro-dents, infection produces chronic and persistent asymptomatic shedding in the renal tubules, and bacteria are then excreted in urine. A wide range of molecular methods to type leptospiral iso