Chemical and Biological Properties of Lipopolysaccharides from Fusobacterium necrophorum Biovar A and Biovar B Strains

Abstract

In order to elucidate factors influencing the virulence of F.necrophorum, studies were performed on chemical and biological properties of lipopolysaccharides (LPSs) obtained from F.necrophorum VPI 2891 (FN 2891) which was biovar A and virulent, and F.necrophorum 130 (FN 130) which was biovar B and avirulent. Chemical analyses revealed marked differences in contents of hexose (21.5% as glucose in FN 2891 LPS and 66.2% in FN 130 LPS), aminosugar (12.9% as glucosamine-HCI in FN 2891 LPS and 0.9% in FN 130 LPS) and lipid A (34.0% in FN 2891 LPS and 4.2% in FN 130 LPS). FN 2891 LPS was more toxic than FN 130 LPS in the lethal effect on 10 day-old chick embryos, the hemorrhagic necrosis of solid tumor (Sarcoma 180), the febrile response of rabbits and the local Shwartzman reaction. No differences were observed in immunogenicity and Limulus lysate test. These results indicated the possibility that LPS was one of factors related to the virulence of F.necrophorum.