Submitted to: Association Official Analytical Chemists Annual Intrl Meeting & Exposition
Publication Type: Abstract Only
Publication Acceptance Date: 9/13/2001
Publication Date: N/A
Technical Abstract: The genus Campylobacter encompasses 16 species of highly diverse microbes, which are commensals in the intestinal tract of mammals as well as frank pathogens. Molecular methods, such as polymerase chain reaction (PCR) have been used to detect, quantitate, and characterize these microbes. Unusual campylobacters may be identified by sequence analysis of genes encoding 16S ribosomal RNA. Because of the limited availability of serotyping reagents genomic methods to differentiate Campylobacter have been developed. In restriction enzyme analysis (REA), chromosomal DNA is digested into thousands of fragments with specific restriction enzymes. Restriction fragment length polymorphism (RFLP) describes southern blot hybridization of the restricted DNA chromosomal fragments. Ribotyping uses probes specific for the genes encoding 16S ribosomal RNA in RFLP analysis. Macrorestriction enzyme analysis or pulsed field gel electrophoresis is similar to REA but generates large chromosomal fragments after restriction enzyme digestion. Although time consuming, PFGE, utilizing the enzymes Kpn and SmaI, is regarded as a sensitive method for epidemiological studies of Campylobacter. PCR-based methods for characterizing Campylobacter include randomly amplified polymorphic DNA (RAPD) assays as well as more sophisticated AFLP protocols. PCR amplification of the fla A gene followed by restriction enzyme digestion of the PCR product (fla A typing) has been used to characterize C. jejuni outbreak strains. Ultimately, the choice of genotyping strategies varies with the resources available and research question raised.