Serotype-specific Monoclonal Antibodies against the H12 Flagellar Antigen of Escherichia coli

Abstract

The flagellar filaments of morphotype E isolates of Escherichia coli characteristically possess an apparent helically arranged sheath structure, surrounding the central core of the filament. Reexamination of the type strains of H-serotypes belonging to morphotype E showed that all but serotype H34 possessed the expected morphology. Heterogeneity was observed in both the diameter of filaments from individual morphotype E strains and in the M , of individual flagellins. There was no apparent correlation between these two features. Monoclonal antibodies (MAbs) of the IgM class were raised against serotype H12 flagella. In Western immunoblotting and agglutination tests, the MAbs recognized the H12 antigen of six isolates with different 0 : K antigen combinations. The MAbs were H-serotype-specific, with no significant reaction with the H-antigens of other morphotype E strains. The location of the serotype-specific H 12 epitope(s) was studied by immunolabelling with colloidal gold markers. The epitope was surface-exposed and appeared to be helically arranged on the flagellar filament. The pattern of colloidal gold labelling was consistent with the possibility that the H12 serotypespecific epitope resides in the apparent sheath structure.

Identification of H-specific determinants in flagellin of four Escherichia coli strains

“…This CVR is not essential for the synthesis and function of flagellum, because a minimum-size functional flagellin with the CVR deleted has been successfully constructed (Homma et al 1987;Kanto et al 1991;Kuwajima 1988a;Kuwajima et al 1989). However, the CVR was shown to carry both H-specific determinants and cross-reactive determinants in E. coli (Feng et al 1990;Kuwajima 1988a;Kwang et al 1996;Schoenhals and Whitfield 1990;Whitfield et al 1988) and in Salmonella (He et al 1994;Ibrahim et al 1985aIbrahim et al , 1985bJoys and Schödel 1991;Langman 1972;Newton et al 1991;Van Asten et al 1995). In H10, the distribution of antigenic sites in flagellin CVR was not immediately clear because the designed fragments were overlapping.…”

“…Nevertheless, serological cross-reactions are frequently observed among different E. coli H-types, for example, H7, H23 and H24 . There have been several studies on the characterization of morphotype E ,H-specific epitopes by using monoclonal antibodies Kwang et al 1996;Schoenhals and Whitfield 1990;Whitfield et al 1988). However, the use of polyclonal antibody to study H-specific determinant(s) in different H-types of E. coli has not been reported.…”

A new type of flagellin gene in Pseudomonas putida.

“…There have been reports that some bacteria inhabiting the mammalian gastrointestinal tract have large flagellins (Nuijten et al, 1990;Wei and Joys, 1985;Whitfield et al, 1988), which suggests that filaments with complex surfaces may enhance bacterial ability to move through mucus or bind to host tissues (Wilson and Beveridge, 1993). However, very little is known about any correlation between bacterial flagellin size and its source.…”

Rapid Immunocapture of Pseudomonas putida Cells from Lake Water by Using Bacterial Flagella

“…However, the amino acid composition and N-terminal sequence indicate a strong similarity to other flagellins. Antigenic variation among different bacterial flagellins has been reported (7,22,23,31,37) and exploited in the serotyping of Salmonella spp. (21).…”