Ultrastructural localisation of lipopolysaccharide-binding sites with peroxidase-conjugated lipopolysaccharides

The localisation of lipopolysaccharide-binding sites on erythrocytes with peroxidase-coupled LPS is described. LPS was isolated from Fusobacterium nucleatum (Fus MC-8) by phenol-water extraction. The LPS was coupled to horseradish peroxidase by the two-step method of Avrameas and Ternynck (1971). The biological and serological activities of the conjugated LPS were compared with those of the native material. Peroxidase could be coupled to LPS without significant loss of endotoxic or serological activity. The LPS-peroxidase conjugate could be demonstrated on erythrocytes by light and electron microscopy.