Reversible expression of motility and flagella in Clostridium chauvoei and their relationship to virulence

Abstract

CIostridium chau woei strain 0 ki nawa produced spontaneous non-mot i I e variants at an unusually high rate (approx. conditions without mutagen. Revertants of non-motile variants were detected at a rate of approximately lo-'. Biochemically, every variant corresponded well with the parental strain. By transmission electron microscopy, three of nine non-motile variants of strain Okinawa were found to be flagellate, while the other six were found to be aflagellate. These phenotypes were confirmed by Western blot analysis using monoclonal antibodies directed against the flagella of C. chauvoei. Moreover, the parental flagellate strain and non-motile flagellate variants were significantly more virulent in mice than non-motile, aflagellate variants. Our results demonstrated that phase variation in motility and flagellation occurs in C. chauwoei, and that the flagella are associated with the full expression of virulence. per generation) under normal

Characterization of flagella genes of Agrobacterium tumefaciens, and the effect of a bald strain on virulence

“…Motility-defective, aflagellated bacteria have been reported to be affected in virulence because of abberations in their host adherence, invasion mechanism, or unknown factors. These include aflagellated Vibrio cholerae (Attridge and Rowley, 1983), Campylobacter jejuni (Wassenaar et al, 1991), Borrelia burgdorferi (Sadziene et al, 1991), Clostridium chauvoei (Tamura et al, 1995) a. Student's t-test was used to determine the probability (P ) that the difference between the paired mean numbers are significant.…”

Decreased Potency of the Vibrio cholerae Sheathed Flagellum To Trigger Host Innate Immunity

“…Among these, flagellum-based motility is one of the more common mechanisms used by motile organisms to move toward preferred sites for colonization typically in the earliest stages of the infection process. Thus, bacterial flagella have been considered an important virulence determinant and flagellum-deficient mutants of several pathogens have been shown to be avirulent (4,18,28,38,45). All bacterial flagella are helical macromolecular structures composed predominantly of a single highly conserved protein called flagellin.…”

A Clostridium difficile gene encoding flagellin The GenBank accession numbers for the sequences reported in this paper are AF065259 (strain 79-685) and AF077341 (strain VPI 10463).

“…It has been suggested that the virulence of C. difficile strains is Clostridium difficile flagellin not solely attributable to toxin production ; other factors such as presence of flagella could contribute to virulence. The role of flagella in microbial pathogenesis factors such as virulence, adherence, invasiveness or colonization has been demonstrated for numerous bacteria (Grant et al, 1993 ;Scherer et al, 1993 ;Zhang et al, 1993 ;Grossman et al, 1995 ;Pruckler et al, 1995 ;Tamura et al, 1995 ;Milton et al, 1996 ;Mobley, 1996 ;Bosshardt et al, 1997 ;Kennedy et al, 1997 ;Rosalski et al, 1997 ;West et al, 1997 ;Feldman et al, 1998). In our experiments in vitro, no inhibition of adherence was shown with antibodies against the recombinant flagellum subunit.…”