Long-term clonal lineages within Campylobacter jejuni O:2 strains from different geographical regions and hosts

The genomic diversity of 11 epidemiologically unrelated strains of Campylobacter jejuni (serotype O:2) isolated from different hosts and different geographical regions in Germany over a period of 15 years was studied and results were compared with the reference strain NCTC11168. By flagellin PCR-RFLP typing six fla types were identified, while macrorestriction analysis with three different restriction enzymes revealed almost identical patterns for two human and one bovine strain, even though they were isolated between 1984 and 1996. Interestingly, the PFGE and fla profiles from strain NCTC11168, which was originally isolated in 1977 from an outbreak case in Worcester (UK), were highly similar or even identical to the profiles of these strains. Besides this, mapping of selective genetic markers to the obtained restriction fragments by Southern blot hybridization showed a conserved localization of the investigated sequences in several strains. Our data confirmed considerable degrees of genomic conservation and the occurrence of long-term O:2 serotype-associated clonal lineages in C. jejuni in different geographical regions and hosts.