Antibodies Against Outer Membrane Proteins in Rabbit Antisera Prepared Against Escherichia coli O26 K60

Abstract

Antibodies directed against the protein constituents of the outer envelope membrane of E. coli O26 K60 were demonstrated in antisera elicited in rabbits against 3 different preparations of the bacterium. Outer membranes solubilized by sodium dodecyl sulfate were applied to the antisera in an interfacial precipitin test, followed by polyacrylamide gel electrophoretic analysis of the resulting immunecomplexes. Protein profiles showed a complete outer membrane protein pattern, indicating the antigenic character of these proteins. Antisera containing antibodies against outer membrane proteins and free of reactive antibodies against lipopolysaccharide showed relatively low agglutinating activities against the bacteria. The antibodies against the protein constituents of the outer membrane belong mainly to the 7S class immunoglobulins, as indicated by 2-mercaptoethanol treatment of the antisera.