Me. Konkel et al., Identification of the enteropathogens Campylobacter jejuni and Campylobacter coli based on the cadF virulence gene and its product, J CLIN MICR, 37(3), 1999, pp. 510-517
Campylobacter jejuni and Campylobacter coli are common causes of gastroente
ritis in humans. Infection with C, jejuni or C. coli is commonly acquired b
y eating undercooked chicken. The goal of this study was to develop specifi
c detection assays for C. jejuni and C, coli isolates based on the cadF vir
ulence gene and its product. The cadF gene from C. jejuni and C, coli encod
es a 37-kDa outer membrane protein that promotes the binding of these patho
gens to intestinal epithelial cells. A fragment of approximately 400 bp uas
amplified from 38 of 40 (95%) C. jejuni isolates and 5 of 6 (83.3%) C, col
i isolates with primers designed to amplify an internal fragment of the cad
F gene. PCR was then used to amplify Campylobacter DNA from store-bought ch
ickens. A 400-bp band was amplified from 26 of the 27 chicken carcasses tes
ted by the PCR-based assay, The CadF protein was detected in every C. jejun
i and C. coli isolate tested, as judged by immunoblot analysis with a rabbi
t anti C. jejuni 37-kDa serum. In addition, methanol-fixed samples of whole
-cell C,jejuni and C, coli Here detected with the rabbit anti-37-kDa serum
by using an indirect-immunofluorescence microscopy assay. These findings in
dicate that the cadF gene and its product are conserved among C. jejuni and
C. coli isolates and that a PCR assay based on the cadF gene may be useful
for the detection of Campylobacter organisms in food products.