Pathogenesis of Campylobacter fetus Infections: Serum Resistance Associated with High-Molecular-Weight Surface Proteins

Pathogenesis of Campylobacter fetus infections. Role of surface array proteins in virulence in a mouse model.

“…Recent reports indicate that C.fetus also causes diarrhea and suggest that the intestinal tract may be its portal of entry into the bloodstream (5). Although the mechanisms by which C. fetus causes systemic infection have not been defined, several in vitro studies indicate that a surface array protein (microcapsule) in wild-type C. fetus strains plays a critical role in the organism's ability to resist both the complement-mediated bactericidal activity in normal human serum and phagocytosis by neutrophils (6)(7)(8). This serum-and phagocytosis-resistance is the probable explanation for the high frequency of extraintestinal infection by C. fetus.…”

“…For a given strain, a single protein usually is predominant (9). After repeated in vitro passage, some isolates lose these S-proteins and become unencapsulated, without change in other proteins (6,7). Previous studies of these unencapsulated mutants showed that loss of these high molecular weight S-proteins was associated with loss of resistance to phagocytosis and normal serum killing (6, 7, 1 1).…”

The use of enzyme-linked immunosorbent assay and immunoblotting for the detection of Campylobacter fetus immunoglobulins in the cervico-vaginal mucus of female cattle

“…venerealis, allowing the resistance to reinfection. Blaser et al (1985) and Blaser et al (1987) showed that this protein migrates up to 100 kDa, it is associated to the resistance of C. fetus to human antibodies, and it is labile when extracted by acid. It can be spontaneously lost when the bacterium is cultivated in vitro (Winter et al 1978, which may have occurred with the C. fetus subsp.…”

A Role of thecspAGene Encoding a Mycolyltransferase in the Growth under Alkaline Conditions ofCorynebacterium glutamicum

“…Due to its location, the S-layer is generally involved in interaction between a bacterial cell and its environment. The Slayers of several pathogenic bacteria have been reported to act as virulence factors by mediating resistance to bactericidal activities 19,20) and adhesion to the extracellular matrix proteins of the host. 21) Furthermore, the S-layers can serve as molecular sieves, and act as additional stability factors in the bacterial cell envelope in both pathogenic and non-pathogenic bacteria.…”