Molecular characterization of Campylobacter spp. isolated from poultry faeces and carcasses in Poland

Campylobacter infection is one of the most common enteric human diseases world-wide but the mechanism of Campylobacter pathogenicity has not been exactly explained yet. One of the main reasons is genotypic, hence phenotypic diversity of the bacterial isolates. The aim of the present study was to perform a molecular characterization of randomly selected C. jejuni and C. coli strains isolated from poultry faeces and carcasses in Poland. Several virulence gene markers were identified by polymerase chain reaction (PCR). Furthermore, genetic typing has also been used by the macrorestriction profiling with pulsed-field gel electrophoresis (PFGE). The results of the present study showed that all analyzed isolates of C. jejuni (n = 24) and C. coli (n = 24) contained the flaA and cadF sequences. On the other hand, the virB11 gene was present only in 6 of 48 (12.5%) of the analyzed isolates, whereas most of the strains contained the cdt genes. Other virulence gene lam linked to Campylobacter invasiveness was present in 34 of 48 (72.9%) strains. The restriction analysis of the whole genome digested with Smal produced three main clonal groups designed as I, II (with two subgroups IIa and IIb), and III obtained by the comparison of macrorestriction profiling patterns. The results showed a poor correlation between Campylobacter profiles generated by a clonal molecular technique and the presence of virulence markers. Therefore, PCR detection of Campylobacter virulence markers can be utilized as a simple and rapid tool to discriminate stains recovered from different sources, especially when used in conjunction with the PFGE profile analysis as a complex strategy. These kinds of analyses had not been previously carried out in Poland and these results may generate more knowledge regarding the genetic diversity and molecular relationship of Campylobacter.