title: Lipopolysaccharide structures of Campylobacter fetus are related to heat-stable serogroups.
abstract: To determine whether lipopolysaccharide (LPS) structures of Campylobacter fetus are related to the three known heat-stable serogroups, proteinase K-treated whole cell lysates obtained from strains of each serogroup were electrophoresed in polyacrylamide gels. All strains had smooth-type LPS with multiple high-molecular-weight repeating units. The profiles of serogroup A from C. fetus subsp. fetus and from C. fetus subsp. venerealis were identical, but they were different from those of C. fetus subsp. fetus serogroups B and AB. When we immunoblotted the LPS of these serogroups with normal or immune rabbit serum we found homologous recognition between serogroups A from C. fetus subsp. fetus and C. fetus subsp. venerealis. Similarly, serogroups AB and B from C. fetus subsp. fetus showed homologous recognition. However, antiserum against serogroup A did not recognize serogroups B and AB and vice versa. Absorption studies confirmed the identity of LPS from all serogroup A C. fetus strains and cross-reactivity of the serogroup B and AB strains with one another. Serogroup A strains were resistant to the bactericidal activity in normal human serum, whereas serogroup B and AB strains generally were susceptible; isolates from humans predominantly belonged to serogroup A. Results of these studies suggest that the LPS composition forms the basis for the heat-stable serotyping system for C. fetus and that the structural and antigenic variants are associated with differential serum susceptibility.
mesh_terms: D000818:Animals; D001770:Blood Bactericidal Activity; D002167:Campylobacter / Q000145:classification / Q000276:immunology*; D002168:Campylobacter fetus / Q000145:classification / Q000276:immunology*; D003429:Cross Reactions; D006358:Hot Temperature; D006801:Humans; D007163:Immunosorbent Techniques; D008070:Lipopolysaccharides / Q000276:immunology*; D011817:Rabbits; D012703:Serotyping
chemical_list: D008070:Lipopolysaccharides