Bacteriophage-resistant mutants of Escherichia coli K12 with altered lipopolysaccharide. Studies with concanavalin A

Three classes of mutants of Escherichia coli K12, isolated by selection for resistance to lipopolysaccharide-specific bacteriophages, were agglutinated by Concanavalin A which is presumed to interact with the lipopolysaccharide component of the outer membrane. Wheat germ and soy bean agglutinins did not agglutinate the parent or mutant strains. The adsorption of certain bacteriophages was also inhibited by Concanavalin A. The pattern of inhibition of adsorption of bacteriophages suggests that non-specific masking of receptors may occur, as well as specific masking of terminal glucose residues. Although bacteria were agglutinated by Concanavalin A, the permeability of the outer membrane seemed unaffected.