title: Purification and properties of Clostridium botulinum type F toxin.
abstract: Clostridium botulinum type F toxin of proteolytic Langeland strain was purified. Toxin in whole cultures was precipitated with (NH4)2SO4. Extract of the precipitate was successively chromatographed on diethylaminoethyl-cellulose at pH 6,0, O-(carboxymethyl) cellulose at pH 4.9, and finally diethylaminoethyl-cellulose at pH 8.1. The procedure recovered 14 percent of the toxin assayed in the starting culture. The toxin was homogeneous by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, double gel diffusion serology, and isoelectric focusing. Purified toxin had a molecular weight of 150,000 by gel filtration and 155,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Specific toxicity was 9.6 X 10-6 mean lethal doses per absorbancy (278 nm) unit. Sub-units of 105,000 and 56,000 molecular weight are found when purified toxin is treated with a disulfide reducing agent and electrophoresed on sodium dodecyl sulfate-polyacrylamide gels. Reciprocal cross neutralizations were demonstrated when purified type F and E toxins were reacted with antitoxins which were obtained with immunizing toxoids prepared with purified toxins.
mesh_terms: D000645:Ammonium Sulfate; D001905:Botulinum Toxins / Q000032:analysis / Q000276:immunology / Q000302:isolation & purification; D011232:Chemical Precipitation; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D003014:Clostridium botulinum / Q000378:metabolism; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D005779:Immunodiffusion; D007525:Isoelectric Focusing; D008970:Molecular Weight; D009500:Neutralization Tests
chemical_list: D001905:Botulinum Toxins; D000645:Ammonium Sulfate