THE CENTRAL, SURFACE-EXPOSED REGION OF THE FLAGELLAR HOOK PROTEIN FLGE OF CAMPYLOBACTER-JEJUNI SHOWS HYPERVARIABILITY AMONG STRAINS

In a previous study, we observed that monoclonal antibodies raised aga inst the hook protein FlgE of Campylobacter jejuni LIO 36, isolate 522 6, bound exclusively to this strain, The aim of this study was to eluc idate the molecular basis for these binding specificities. The hook pr otein-encoding gene flgE of C. jejuni was cloned in Escherichia coli a nd sequenced. The flgE genes of four additional C. jejuni strains were amplified by PCR and also sequenced. Comparison of the deduced amino acid sequences revealed a high degree of variability in the central pa rts of the FlgE proteins among the strains, including variable and hyp ervariable domains. These findings may indicate a selective pressure o f C, jejuni hosts, forcing the bacteria to generate variations in surf ace exposed antigenic determinants.