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    Investigation of Virulence and Cytolethal Distending Toxin Genes in Campylobacter spp. Isolated from Sheep in Turkey
    (MARY ANN LIEBERT INC, 2013) Acik, Mehmet N.; Karahan, Murat; Ongor, Hasan; Cetinkaya, Burhan
    The presence of virulence and cytolethal distending toxin (Cdt) genes was investigated in isolates of Campylobacter jejuni, C. coli, C. lanienae, and C. lari that originated from intestinal contents and gallbladders of clinically healthy sheep. These genes have important roles in the pathogenicity of campylobacters. A total of 363 Campylobacter isolates (221 C. jejuni, 135 C. coli, five C. lanienae, and two C. lari) were used in this study. The frequency of racR, dnaJ, ciaB, pldA, flaA, and cadF virulence genes in all the isolates were determined to be 34.4%, 30%, 24.8%, 30.9%, 95%, and 81.3%, respectively, while the virB11 virulence gene could not be detected in any isolates. CdtA, cdtB, and cdtC genes were detected in 54.5%, 55.9%, and 52.3% of the isolates, respectively. None of the virulence and toxin genes examined here were detected in a total of 19 Campylobacter isolates consisting of 10 C. jejuni and nine C. coli. This is the first study investigating the presence of virulence and toxin genes in a large number of Campylobacter species isolated from clinically healthy sheep by scanning a large area. In addition, this is the first report investigating the presence of virulence and toxin genes in sheep-originated C. lanienae and C. lari isolates.
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    Isolation and Molecular Characterization of Escherichia coli O157 from Broiler and Human Samples
    (Mary Ann Liebert Inc, 2012) Kalin, Recep; Ongor, Hasan; Cetinkaya, Burhan
    There is a lack of information about the role of poultry, specifically chicken, in transmission of Escherichia coli (E. coli) O157 and subsequent human illnesses. This study was therefore aimed at investigating the presence of E. coli O157 and its virulence genes in various samples collected from broiler chickens and humans in Eastern Turkey by culture, immunomagnetic separation (IMS), and polymerase chain reaction (PCR). The genetic relationship between broiler and human isolates was also examined by pulsed-field gel electrophoresis (PFGE). In the PCR analysis of sorbitol-negative isolates, E. coli O157 was identified in 0.1% (1/1000) and 0.4% (4/1000) of the liver and cecum samples of broiler chickens, respectively. On the other hand, none of the carcass samples were determined to be positive for E. coli O157. Overall, the results indicated that 12% (3/25) of the flocks were positive for E. coli O157. The differences between the flocks in terms of the positivity were determined to be statistically significant (p < 0.001). Ten (2.7%) of 367 human stool samples were also positive for E. coli O157 in the PCR examination. None of the broiler and human E. coli O157 isolates possessed H7, shigatoxins 1-2, or enterohemolysin genes, whereas all the broiler isolates and one of the human isolates were positive for intimin gene. In the PFGE analysis, a total of eight different profiles (four from broiler and four from human isolates) were observed. However, there were no genetic relationships between broiler and human E. coli O157 isolates. It can be concluded that more detailed studies are needed in poultry to better understand the role of these species in the epidemiology of E. coli 0157 infections in humans.