Extracellular Antigens from Listeria monocytogenes I. Purification and Resolution of Hemolytic and Lipolytic Antigens from Culture Filtrates of Listeria monocytogenes.

Two antigens were purified from culture filtrates of Listeria monocytogenes 7973 by the following procedure: (i) acid precipitation with 4 n HCl at pH 3.7, (ii) Sephadex G-75 column fractionation, (iii) diethylaminoethyl-Sephadex A50 batchwise adsorption, and (iv) rechromatography on Sephadex G-75. This procedure resulted in the resolution of two distinct antigens. One antigen, designated a hemolytic antigen because of its ability to lyse erythrocytes from a variety of species, had a specific activity of 25,000 units/mg of protein and an estimated molecular weight of at least 171,000. The other antigen, designated a lipolytic antigen because of its ability to hydrolyze egg yolk saline substrate, had a specific activity of 400 units/mg of protein and an estimated molecular weight of 52,500.