A shift in the virulence potential of Corynebacterium pseudotuberculosis biovar ovis after passage in a murine host demonstrated through comparative proteomics

Abstract

Background Corynebacterium pseudotuberculosis biovar ovis, a facultative intracellular pathogen, is the etiologic agent of caseous lymphadenitis in small ruminants. During the infection process, C. pseudotuberculosis changes its gene expression to resist different types of stresses and to evade the immune system of the host. However, factors contributing to the infectious process of this pathogen are still poorly documented. To better understand the C. pseudotuberculosis infection process and to identify potential factors which could be involved in its virulence, experimental infection was carried out in a murine model using the strain 1002_ovis and followed by a comparative proteomic analysis of the strain before and after passage.ResultsThe experimental infection assays revealed that strain 1002_ovis exhibits low virulence potential. However, the strain recovered from the spleen of infected mice and used in a new infection challenge showed a dramatic change in its virulence potential. Label-free proteomic analysis of the culture supernatants of strain 1002_ovis before and after passage in mice revealed that 118 proteins were differentially expressed. The proteome exclusive to the recovered strain contained important virulence factors such as CP40 proteinase and phospholipase D exotoxin, the major virulence factor of C. pseudotuberculosis. Also, the proteome from recovered condition revealed different classes of proteins involved in detoxification processes, pathogenesis and export pathways, indicating the presence of distinct mechanisms that could contribute in the infectious process of this pathogen.ConclusionsThis study shows that C. pseudotuberculosis modifies its proteomic profile in the laboratory versus infection conditions and adapts to the host context during the infection process. The screening proteomic performed us enable identify known virulence factors, as well as potential proteins that could be related to virulence this pathogen. These results enhance our understanding of the factors that might influence in the virulence of C. pseudotuberculosis.Electronic supplementary materialThe online version of this article (doi:10.1186/s12866-017-0925-6) contains supplementary material, which is available to authorized users.

Prevalence and molecular investigation of caseous lymphadenitis among the slaughtered sheep at Duhok Abattoirs; experimental infection with Corynebacterium pseudotuberculosis in rabbits

“…No study was found on rabbits to compare the present data with; C. pseudotuberculosis biovar ovis strain were isolated after 36 hr post-infection from spleen of mice after intraperitoneally injected with 10 6 CFU/ml (43). Besides, four different equine-origin Corynebacterium pseudotuberculosis strains C3H/HeJ were isolated from liver, spleen, lungs, and mesenteric lymph nodes of mice following intradermal injection (14).…”

Linfadenitis caseosa: factores de virulencia, patogénesis y vacunas. Revisión

“…La cepa 1002 atenuada, tras varios pases en un modelo murino fue capaz de revertir la virulencia. El análisis por espectrometría de masas permitió la identificación de las proteínas PLD y CP40 únicamente, en la cepa 1002 reactivada, lo que indica la participación de estas proteínas en la virulencia (51) . Por otra parte, a través de PCR en tiempo real se identificó in vitro e in vivo la expresión de varios genes involucrados en la virulencia entre ellos pld y cp40.…”

Co-Expression Networks for Causal Gene Identification Based on RNA-Seq Data of Corynebacterium pseudotuberculosis

“…In the past few years, several genomic, transcriptomic, and proteomic studies have been performed to understand the biological basis of Corynebacterium pseudotuberculosis; these studies allowed the identification and understanding of the genomic mechanisms that contribute to the virulence and infection processes used by the bacteria [1][2][3][4][5][6][7]. C. pseudotuberculosis is a Gram-positive intracellular bacteria and the etiologic agent of caseous lymphadenitis, a chronic, pyogenic, and contagious disease that affects small ruminants causing considerable economic losses for the farmers and meat industries in many countries [5,8].…”