Heat shock stress: Profile of differential expression in Corynebacterium pseudotuberculosis biovar Equi.

ABSTRACT

Transcriptome studies on Corynebacterium pseudotuberculosis have recently contributed to the understanding about this microorganism's survival mechanisms in various hostile conditions. The gene expression profile of the C. pseudotuberculosis strain 1002 (Ovis biovar), has revealed genes that are possible candidates responsible for its maintenance in adverse environments, such as those found in the host. In another strain of this bacterium, 258 (Equi biovar), a high temperature condition was simulated, in order to verify which genes are responsible for promoting the persistence of the bacterium in these conditions, since it tolerates temperatures higher than 40°C, despite being a mesophilic bacterium. It was possible to generate a list of genes using RNAseq technology that possibly contribute to the survival of the bacteria in this hostile environment. A total of 562 genes were considered as differentially expressed, then, after the fold-change cutoff, 113 were considered induced and 114 repressed, resulting in a total of 227 genes. Therefore, hypothetical proteins presented a fold change above 6, and genes characteristically in control for this type of stress, such as hspR, grpE, and dnaK, presented a fold change above 3. The clpB gene, a chaperone, drew attention due to presenting a fold change above 3 and located in a pathogenicity island. These genes may contribute towards efficient solutions to the effects caused by ulcerative lymphangitis in equines, thus attenuating the damage it causes to agribusiness.