Rapid identification of Campylobacter jejuni strains by polymerase chain reaction & their restriction fragment length...

A polymerase chain reaction (PCR) technique was developed for specific identification of C. jejuni. A primer pair of a conserved region of flagellin A (fla A) gene identified all 15 strains of C. jejuni isolated from human faeces. None of the control strains like Helicobacter pylori, Vibrio cholerae Escherichia coli and Salmonella typhimurium except C. coli exhibited any amplified product by PCR. A predicted 450 bp could also be amplified from 4 chicken caecal contents positive for C. jejuni-C coli by culture. The caecal contents remained positive for C. jejuni-C. coli by PCR after preservation at 4 degrees C for one week when no viable organism could be detected. Restriction fragment length polymorphism analysis (RFLP) of fla A amplified product by using Bgl II enzyme classified 15 strains into 5 types. Three C. jejuni strains isolated from the same patient over a period of 3 wk showed the same RFLP pattern. The present study indicates that PCR is specific for C. jejuni-C. coli and it has the potential for rapid diagnosis of infection. RFLP can be a good epidemiological marker for C. jejuni infection.