Electron microscopy of the combination of antibodies with flagellar antigen and with a pyocine.

Micrographs are presented of antibodies in combination with flagella of Salmonella typhi and with a phage-bound pyocine Rmc, which is supposed to be the tail of a defective bacteriophage from Pseudomonas aeruginosa. The pyocine preparation seems to offer advantages for the study of antibody-antigen complexes. Under the conditions of our experiments, the surfaces of the antigenic structures are saturated with antibody layers approximately 95 A in thickness, i.e., slightly less than half the accepted lengths of 7S antibody molecules. Our interpretation is that the antibody is attached by combining sites at the ends of the molecules to form loops along the surface of the antigenic structures.