Isolation and characterization of the flagellar hook of Campylobacter jejuni

Abstract

A method for purification of the flagellar hook of Campylobacter jejuni is described. The hook was shown to be composed of a subunit protein, which has a molecular mass of 92,000 and an isoelectric point of pI 4.8. A monoclonal antibody and a polyvalent antiserum was raised against the purified flagellar hook of C. jejuni. Immuno-electronmicroscopy revealed that the epitope recognized by the monoclonal antibody is surface-located. However, this antibody reacted only with the hook of the immunization strain, but not with other strains or other flagellated bacteria. Thus, our data indicate that the immunodominant epitopes are located on the surface of the hook and that these epitopes are strain-specific.

Flagellar-Dependent Motility in Mesorhizobium tianshanense is Involved in the Early Stage of Plant Host Interaction: Study of an flgE Mutant

“…By contrast, fewer amino acid sequence similarities are observed in the central part of the hook protein. In Campylobacter jejuni, the sequence of the central part of the hook protein varies greatly among different species and even in one serotype, and the corresponding domains are likely to be exposed to the surface based on the immunoelectron microscopy observation that MAbs bind to the intact hook [10]. These observations suggest that the conserved and variable characteristics in the hook protein sequence play an important role in hook structure consensus and immune diversity.…”

The Central, Surface-Exposed Region of the Flagellar Hook Protein FlgE of Campylobacter jejuni Shows Hypervariability among Strains

“…In C. jejuni, the large central region of the hook protein exhibits hypervariability among strains of one species and even of one serotype. The variable and hypervariable domains are likely to be exposed to the surface, since immunoelectron microscopy reveals that the MAbs employed in our studies bind to the intact hook (6). The surface exposure of variable domains may reflect the need of C. jejuni to generate antigenic diversity.…”

“…None of the MAbs reacted with any other tested C. jejuni LIO 36 strain. Likewise, the MAbs did not bind to any tested C. jejuni strain of other LIO serotypes (6). The aim of this study was to elucidate the molecular basis of this binding specificity.…”

“…In a previous study in our laboratory, monoclonal antibodies (MAbs) were raised against the purified hook of C. jejuni LIO 36, clinical isolate 5226 (6). All of these MAbs bound exclusively to that strain, from which the hook had been isolated and used for immunization of mice.…”

“…Screening of colonies for expression of the flgE gene was done with MAb 02B5 by colony blotting, performed essentially as described elsewhere (21). MAb 02B5 had been raised against the purified hook filament of C. jejuni LIO 36, isolate 5226 (6). The 02B5-reactive clone DH5␣(pCAH32) was isolated and further analyzed.…”