ENVIRONMENTAL FACTORS AFFECT THE SURVIVAL AND EXPRESSION OF VIRULENT CYTOLETHAL DISTENDING TOXIN OF Campylobacter jejuni
نویسندگان
چکیده
Several environmental factors regulate the expression of virulence genes under certain conditions and the expression of bacterial virulence determinants. Cytolethal distending toxin (CDT) is an important virulence determinant secreted by Campylobacter jejuni (C. jejuni), a leading cause of gastrointestinal bacterial pathogen worldwide. Therefore, the aim of the study was to investigate the effect of selected environmental stress factors such as temperature, pH and proteolytic enzymes on cytotoxicity of culture supernatants containing CDT activity of 10 C. jejuni strains [5 CDT (-ve) and equal number of randomly selected CDT (+ve) C. jejuni strains] using Hep-2 and HeLa cells. Additionally, after stress exposure, adhesion, invasion and intracellular survival of C. jejuni were also studied.
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