INVESTIGADORES
RUYBAL paula
congresos y reuniones científicas
Título:
Phylogenomics of Leptospira interrogans: SNPs finding for epidemiological purposes
Autor/es:
VARNI VANINA; AMADIO ARIEL; NAGEL ARIEL; RUYBAL PAULA; CAIMI KARINA
Lugar:
Antwerp
Reunión:
Congreso; 13th International Conference on Molecular Epidemiology and Evolutionary Genetics of Infectious Diseases; 2016
Resumen:
IntroductionLeptospira interrogans is the main etiological agent of Leptospirosis worldwide. The species comprises more than 250 pathogenic serotypes transmitted through contact with water contaminated by urine of carrier animals.Serological typing is both complex and inaccurate. Our group is focused on finding new tools for molecular typing based on whole genomic sequencing (WGS).In this work, we performed WGS of isolates that belong to the predominant serotypes in Argentina, Pomona and Canicola, and compared them with worldwide genomes from these same serotypes. The aim was to identify SNPs that enable an accurate discrimination among closely related isolates from the same serotype, and also bring new insights to the epidemiology of this pathogen.MethodsTwo Leptospira interrogans isolates from Argentina were selected for genome sequencing, using an Illumina platform. Those belonged to serogroups Pomona and Canicola. Additionally we downloaded from public databases 8 and 6 genomes of each serogroup, isolated in different countries. The alignment of the 16 total genomes with a reference strain (L. interrogans sv. Cophenageni) allowed the identification of polymorphic positions (SNPs) which were further explored through phylogenetic analysis.ResultsThe SNPs identified were concatenated and used as input sequence for a phylogeny. The resulting tree showed 2 distinguishable clusters corresponding to the serogroups included, but also subclusters of strains within each serogroup, improving the discrimination. The subclustering of isolates was closely related to their geographic origins.DiscussionThe comparison of local Leptospira genomes in a worldwide context of genomes allowed the identification of SNPs, both within serogroup as among serogroups. These SNPs arise as a promising perspective for local and global epidemiology of Leptospira, leading to the discrimination of isolates that could not be achieved by traditional molecular markers. Also, the phylogenomics approach may provide new clues on the epidemiological connections among different isolates around the world.