a new purification method for beta-toxin of clostridium perfringens type c vaccinal strain

background : clostridium perfringens type c strains cause severe necrotizing enteritis in sheep, calves, goats, pigs and humans. beta-toxin is introduced to be the essential virulence factor of this microorganism. in the present study, a new method was established for the purification of beta toxin from culture supernatant fluid of c. perfringens type c vaccinal strain. methods : the four steps of the purification scheme involved ammonium sulfate precipitation, cation exchange chromatography (cm- sepharose), anoion exchange chromatography (deaecellulose) and gel filtration (sephadex g-100). results : beta toxin was purified about 78-fold from the sephadex g-100 column with a yield of about 16.7% in terms of lethality of the toxin. the molecular weight of the beta toxin as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis was approximately 37 kd. the ld50 for adult mice was 2.21 μg/kg. human umbilical vein endothelial cells (huvec) exposed to cpb showed a cell border retraction, cytoplasmic blebbing, cell shrinkage and cell rounding. the toxin was heat labile and was inactivated by trypsin. conclusions : in conclusion, the results of this study showed the new protocol is suitable for purification of beta toxin of c. perfringens type c regarding good purity, good yields and high activity of beta toxin.