title: Oral toxicities of Clostridium botulinum type C and D toxins of different molecular sizes.
abstract: Clostridium botulinum type C progenitor toxins of different molecule sizes, C-L (16S) and C-M (12S), were purified from cultures of strains 573, Stockholm, and CB-19. C-L toxin showed some hemaggglutinin activity, whereas C-M toxin did not. Neither C-L nor C-M toxin was activated upon trypsinization. Molecular dissociation of purified type C-L and C-M toxins into toxic and nontoxic components was demonstrated by sucrose density gradient ultracentrifugation and diethylaminoethyl-Sephadex chromatography at pH 8.0. The molecular construction of type C progenitor toxin appears to be analogous to that reported for botulinum toxins of other types. C-L and D-L toxins showed higher oral toxicities to mice than did C-M or D-M toxin. Such higher oral toxicities were ascribed to the higher stabilities of these toxins in gastric and intestinal juices.
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001905:Botulinum Toxins / Q000302:isolation & purification / Q000494:pharmacology / Q000633:toxicity*; D002850:Chromatography, Gel; D005750:Gastric Juice / Q000187:drug effects; D007274:Injections, Intraperitoneal; D007275:Injections, Intravenous; D007422:Intestines / Q000187:drug effects; D007928:Lethal Dose 50; D008297:Male; D051379:Mice; D051381:Rats
chemical_list: D001905:Botulinum Toxins