Genômica comparativa entre os biovares Equi e Ovis de Corynebacteriumpseudotuberculosis isolados no México

Abstract

Next generation sequencing (NGS) technologies development haveallowed study fields such as comparative genomics to grow and led to a better comprehension of different organisms. Among those, we can highlight pathogenic bacteria such as Corynebacterium pseudotuberculosis, which can be divided in two biovars. The ones belonging to biovar Ovis affect mainly small ruminants and ones belonging to biovar Equi affects larger animals such as equines, buffaloes and cattle. These diseases have been causing huge financiallosses in the global agribusiness. In this work, six strains of C.pseudotuberculosis isolated from goats, sheep and horses from Mexico were studied; this is the first in silico research concerning strains of this organism isolated from this country. The genomic DNAs were sequenced by using Ion PGM sequencing technology, followed by the assembly, annotation and deposit of the resulting genomes at NCBI. In the comparative genomics studies, the following software were used: Protein Family Sorter from PATRIC (pangenome), Gegenees and FigTree (generation of phylogenomic tree), GIPSy and BRIG (prediction and visualization of pathogenic islands (PAIs), respectively) and the Specialty Genes Search tool from PATRIC (prediction of drug targets).In the pan-genome analyses of the six organisms, the value of the pan-genome was 2295, the core genome was 1903, the accessory genome was 343 and the singletons was 49. Concerning the phylogenomic analyses, it was noticed that the strains clustered by biovar, and the strains from the same host present higher genomic similarity. In accordance with the phylogenomic results, it wasfound similarities by biovar in the PAI analysis, and one of the found PAIs was present in all organisms. Furthermore, it was found a putative drug target in five out of six studied genomes. This work aimed to contribute with the biological knowledge of C. pseudotuberculosis and in the identification of putative virulence factors that can be used in researches that focus in the development of vaccines and drugs for eradication of different diseases caused by this organism.