Immunoblot and enzyme-linked immunosorbent assays of Campylobacter major outer-membrane protein and application to the differentiation of Campylobacter species

Abstract

The major outer-membrane protein (MOMP) from Campylobacter jejuni NCTC 11168 was purified by solubilization in Triton X-100. Whole-cell proteins of Campylobacter species and the MOMP were subjected to electrophoresis on sodium dodecyl sulfate-polyacrylamide gels, immunoblotting on nitrocellulose paper and enzyme-linked immunoblot assay (ELISA) analyses using polyclonal antiserum to the C. jejuni MOMP. Purified MOMP from C. jejuni NCTC 11168 contained a single major protein of 46 kDa. Whole-cell preparation of C. jejuni NCTC 11168 also showed a major band of 46 kDa which was recognized in immunoblots by the anti-MOMP serum. Other C. jejuni strains, as well as C. coli and C. laridis strains showed similar MOMP bands at 45-46 kDa. Other Campylobacter species (C. fetus ss. fetus, C. hyointestinalis and C. pylori (new nomenclature] did not react in immunoblots with antiserum to the C. jejuni MOMP. ELISAs showed that antiserum raised against the C. jejuni MOMP reacted with C. jejuni, C. coli and C. laridis strains. Other Campylobacter species displayed only a very low degree of cross-reactivity. The distinct antigenic relationship demonstrated between the MOMP of C. jejuni, C. coli and C. laridis is consistent with the close degree of relatedness of these species as determined by DNA homology studies. The anti-MOMP serum appeared to be useful in the rapid differentiation of C. jejuni, C. coli and C. laridis from other Campylobacter species.