Phylogenetic Studies of Campylobacter jejuni Using Arbitrary Primer-PCR Fingerprinting

Abstract

Over the years several typing systems have been developed as tools for the study of the epidemiology of Campylobacter to identify common sources and characterize outbreaks. Until now, typing systems have been based on the use of heat-labile (Lior)³ and heat-stable (Penner)⁸ antigens. However, these systems are restricted to reference centers, and there are an important number of non-typable strains, mainly among those were isolated in developing countries or from domestic animals. In addition, these typing methods have inherent limitations to differentiate strains with the same serotype. Recently developed methods include ribotyping⁵, electrophoresis of whole bacterial proteins, pulse field gel electrophoresis of total DNA, and restriction fragment length polymorphism (RFLP) of PCR-amplified fragments of the flagella gene^4,2, which have proved to be useful to determine relatedeness between strains of C. jejuni isolates from different sources and origins. Most of these methods are slow, cumbersome and expensive. In this study, we used the arbitrary primed PCR technique⁹, with which it is possible to generate polymorphism of total genomic DNA of Campylobacter, to perform hierarchical analysis of strains, and we were able to identify not only strains from the some source in outbreaks, but also to group strains from different geographic areas and to distinguish between human and non-human isolates.