All isolates of this study were PCR-positive for ciaB and the cdtB. The C. jejuni isolates were cultured on Columbia agar base (Merck) supplemented with 5% sheep blood (BA) and incubated at 42°C under microaerophilic conditions (5% O2, 10% CO2, 85% N2) for 24 hours prior to DNA extraction. DNA extraction and marker gene detection Genomic DNA of C. jejuni was isolated using the QIAamp DNA Mini Kit (Qiagen) according to the manufacturer’s instructions. For detection of the different genetic markers the primers listed in Table2 were used. Phylogenetic analysis For construction of a UPGMA-dendrogram (unweighted-pair
group method using average linkages) the MEGA4 software was used [21], and the LY2109761 C. jejuni MLST website (http://pubmlst.org/campylobacter/) developed by Keith Jolley and Man-Suen Chan, sited at the University of Oxford was consulted for assignation of sequence types and LY3023414 clonal complexes [22]. Statistical analyses Statistical analysis was performed using the Statistica software. The χ²-test was used to test for significant differences/similarities in the frequencies
of the various genetic markers within the defined groups. The obtained p-values are indicated in Table1. Acknowledgements The authors’ work was supported by the Deutsche Forschungsgemeinschaft (DFG GR906/13-1) and the Forschungsförderungsprogramm BI 2536 chemical structure of the Universitätsmedizin Göttingen (UMG), Germany. This publication was funded by the Open Access support program of the Deutsche Forschungsgemeinschaft and the publication fund of the Georg August Universität Göttingen. References 1. Zautner AE, Herrmann S, Groß U: Campylobacter jejuni – The search for virulence-associated factors. Arch Lebensmittelhyg 2010, 61:91–101. 2. Zautner AE, Herrmann S, Corso J, Tareen AM, Alter T, Groß U: Epidemiological association of different Campylobacter jejuni groups with metabolism-associated genetic markers. Appl Environ Microbiol 2011, 77:2359–2365.PubMedCrossRef 3. Habib I, Louwen R, Uyttendaele M, Houf K, Vandenberg O, Nieuwenhuis EE, Miller WG, van Belkum A, De Zutter L: Correlation between genotypic diversity, lipooligosaccharide
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