The role of lysozyme in killing and lysis of coliform bacteria in the bovine animal 2. Effect of absorbing serum with bentonite or bacteria

Adding lysozyme in the presence of EDTA to bentonite-absorbed serum produced variable results in bacteriolytic tests either restoring lytic activity, potentiating existing activity or not affecting activity depending on the organism and serum used. Bactericidal activity, when removed by bentonite, was not restored by adding lysozyme. Absorbing sera with bacteria removed both bacteriolytic and bactericidal activity, the amount removed depending on the number of absorptions. Bacteriolytic, but not bactericidal, activity of sera absorbed with bacteria was restored by added lysozyme in the presence of EDTA. Serum absorbed with zymosar or antigen— antibody precipitates is inactive in bacterial killing.A requirement for added C′ in the bactericidal system can only be demonstrated in high dilutions of serum suggesting that C′ activity rather than antibody is the limiting factor.The experiments show that absorption techniques for removing lysozyme or antibody are non-specific and that lysozyme is involved in lysis but not in the killing of coliforms by bovine serum.