Molecular investigation of salmonella choleraesuis and salmonella hadar strains isolated from humans in Turkey.

Eleven Salmonella Choleraesuis and seven Salmonella Hadar strains isolated from various clinical humand samples were investigated by plasmid profile analysis, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and pulsed-field gel electrophoresis (PFGE) in order to obtain information at a molecular level on the epidemiology of S. Choleraesuis and S. Hadar, which are significantly present in Turkey. Plasmid profile analysis showed that 10 (90.9%) of 11 S. Choleraesuis isolates harbored one to two plasmids with sizes of 2.0, 5.0 or 6.5 kb; and 5 (71.4%) of 7 S. Hadar isolates harbored one to three plasmids ranging from 2.5 to 70 kb. ERIC-PCR was performed using ERIC-2 primers; since isolates within each serotype showed similar band models, we concluded that ERIC-PCR is not suitable for differentiating isolates within the same serotype and for grouping into clusters. In PFGE using the AvrII enzyme, S. Choleraesuis isolates formed three clusters, and S. Hadar isolates formed three clusters; using the XbaI enzyme, S. Choleraesuis isolates formed two clusters, and S. Hadar isolates formed four clusters. These results showed that plasmid profile analysis and PFGE are reliable and discriminative methods that would complement antibiograms, and could contribute to the investigation of outbreak epidemiology. This is the first report on S. Choleraesuis and S. Hadar isolates from Turkey investigated by plasmid profile analysis, ERIC-PCR and PFGE methods.