Medycyna Wet. 67 (11), 725-732, 2011

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Szewczyk R. Wieczorek K., Osek J.
Molecular mechanisms of pathogenicity of thermotolerant Campylobacter
Thermotolerant bacteria belonging to the Campylobacter genus are one of the most common etiological factors of human food-borne infections. The main cause of the human illness is the ingestion of undercooked poultry meat, and the microorganism most commonly isolated from patients is C. jejuni. Every year the number of confirmed cases of campylobacteriosis increases in both developing and developed countries. The acute form of the disease manifests itself with a headache, abdominal pains, vomiting and, in some cases, bloody diarrhea. Campylobacteriosis can lead to serious complications, including the Miller-Fisher syndrome or Reiter’s disease. The mechanism of infection is not yet fully understood, and therefore it is difficult to reduce the number of cases. The problems are related to high genetic variability among bacterial isolates. Several studies conducted in recent years are focused on clarifying the molecular basis of campylobacteriosis. The sequencing of the genome of C. jejuni NCTC 11168 and research conducted on Campylobacter mutants have made it possible to define specific markers playing a role in the virulence of these bacteria. A detailed understanding of the pathogenicity mechanisms of Campylobacter will make it possible to develop better methods of protection against the pathogen and more effective treatment methods. The present paper summarizes the results of recent research on the pathogenecity of Campylobacter, including a characterization of surface structures of bacterial cells (capsule and LOS) and their adaptability to the environment in which they exist, as well as the possibility of adhesion and penetration into the host’s intestinal epithelial cells. Flagella and proteins, such as PEB and CadF, play an important role as adhesions factors. Characteristic of Campylobacter is the process of N-linked glycosylation, which modifies about 30 proteins involved in the colonization, adhesion and invasion of epithelial cells. These bacteria produce two kinds of toxins, of which the best known is cytolethal distending toxin (CDT), which destroys the intestinal epithelium and thereby causes bloody diarrhea in humans.
Keywords: Campylobacter, virulence, adhesion, cytolethal distending toxins CDT