ISOLATION, CLONING AND PHYLOGENETIC ANALYSIS OF pld AND cp40, VIRULENCE FACTORS OF A MEXICAN ISOLATE OF Corynebacterium pseudotuberculosis ovis

Abstract

Background. Caseous lymphadenitis is a worldwide distribute disease that affects the sheep and goat industry. Corynebacterium pseudotuberculosis ovis is a facultative intracellular Gram-positive bacterium, considered the etiologic agent of the disease. Complete genome sequences of Mexican isolates have been obtained and different strain has been previously characterized. The study of virulence factors allows establishing potential candidates for the development of vaccines and diagnostic tools. Objective. To identify the complete pld and cp40 genes sequence from a Mexican isolate of Corynebacterium pseudotuberculosis ovis, principal virulence factors. Methodology. Corynebacterium pseudotuberculosis isolate 2J-L was obtained from an abscess of a sheep of the State of Jalisco. The complete pld and cp40 genes were amplified by PCR, cloned into a replicative vector and sequenced by Sanger automatic sequencing. Gene sequences conservancy was established, analyzing homology across previously reported genes of Mexican strains MEX1, MEX2, MEX9, MEX25 and MEX29. Results. Sequences of pld and cp40 genes from isolate 2J-L presented high percentages of similarity (99%) in comparison with the sequences of other isolates of Corynebacterium pseudotuberculosis, reported in the GenBank database. The analysis of nucleotide sequence homology and phylogenetic tree based on pld and cp40 directed the observation that 2J-L is related to Mexican strain MEX29 and MEX25. Phylogenetic results agreed on the idea that strains biovar ovis and biovar equi are groupings on different clades. Finally, results indicate that Mexican strains are more similar among strains isolated from the same host type, without geography distance influence. Implications. The analysis pointed out that both genes conserve their sequences in comparison with Mexican and international strains, which encourages the research continuity for vaccine and diagnostic tools development using proteins PLD and CP40 as antigen targets. Conclusions. The complete pld and cp40 genes from Mexican isolate 2J-L were amplified, cloned and analyzed; important virulence factors from Corynebacterium pseudotuberculosis.