STUDIES ON ϵ-PROTOTOXIN OF CLOSTRIDIUM PERFRINGENS TYPE D
Purified prototoxin of Clostridium perfringens type D was separated by column chromatography on CM-cellulose or DEAE-cellulose into two and three fractions respectively. The fractions exhibited prototoxin activity and showed immunochemical identity. The purified prototoxin gave a single component in the ultracentrifuge with a sedimentation constant of 2.85 S. The molecular weight was 25,100 ± 1500 and 23,200 when determined by the Archibald method and from sedimentation and diffusion constants respectively. Although the prototoxin was homogeneous by paper electrophoresis and moving boundary electrophoresis at pH 4.5, its heterogeneity was demonstrated on moving boundary electrophoresis at pH 8.6; 72% of material had a mobility of −1 × 10−5 cm2/v sec and 28% with a mobility of −2.7 × 10−5 cm2/v sec. The electrophoretic heterogeneity was also demonstrated on starch gel and disc electrophoresis. Amino acid analysis showed the presence of hydroxyproline and four uncommon amino acids; two of the latter were identified tentatively as hydroxylysine and allohydroxylysine.