Comparison of 23S polymerase chain reaction–restriction fragment length polymorphism and amplified fragment length polymorphism techniques as typing systems for thermophilic campylobacters

Abstract In this study, we evaluated the combination of polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) and amplified fragment length polymorphism (AFLP) molecular typing techniques for the analysis of thermophilic campylobacter species isolated from clinical and poultry samples. 23S PCR–RFLP analysis performed to fingerprint 69 strains exhibited an excellent level of typability. Eleven different types were defined at 100% linkage level following numerical analysis of band patterns. Differentiation of Campylobacter jejuni and Campylobacter coli at species level was achieved although no significant relationship could be observed between the profiles and the origin of the strains. Simplified AFLP analysis of the isolates disclosed the presence of 66 different banding patterns. The resulting dendrogram showed a high diversity among the strains studied. All the isolates were grouped within eight main types with a 69% homology degree among them. Differentiation at subspecies level was possible but no significant relationship could be observed between the AFLP profiles and the origin of the strains. When used in combination, 23S PCR–RFLP and single-enzyme AFLP methods can be applied to determine taxonomic and epidemiological relationships among thermophilic campylobacters.