title: Sporulation and enterotoxin production by mutants of Clostridium perfringens.
abstract: The ability of Clostridium perfringens type A to produce an enterotoxin active in human food poisoning has been shown to be directly related to the ability of the organism to sporulate. Enterotoxin was produced only in a sporulation medium and not in a growth medium in which sporulation was repressed. Mutants with an altered ability to sporulate were isolated from an sp(+) ent(+) strain either as spontaneous mutants or after mutagenesis with acridine orange or nitrosoguanidine. All sp(0) (-) mutants were ent(-). Except for one isolate, these mutants were not disturbed in other toxic functions characteristic of the wild type and unrelated to sporulation. A total of four of seven osp(0) mutants retained the ability to produce detectable levels of enterotoxin. None of the ent(-) mutants produced gene products serologically homologous to enterotoxin. A total of three sp(-) mutants, blocked at intermediate stages of sporulation, produced enterotoxin. Of these mutants, one was blocked at stage III, one probably at late stage IV, and one probably at stage V. A total of three sp(+) revertants isolated from an sp(-) ent(-) mutant regained not only the ability to sporulate but also the ability to produce enterotoxin. The enterotoxin appears to be a sporulation-specific gene product; however, the function of the enterotoxin in sporulation is unknown.
mesh_terms: D000818:Animals; D001681:Biological Assay; D003016:Clostridium perfringens / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism / Q000472:pathogenicity; D003470:Culture Media; D004768:Enterotoxins / Q000096:biosynthesis* / Q000494:pharmacology; D004890:Erythema / Q000139:chemically induced; D005827:Genetics, Microbial; D006168:Guinea Pigs; D006867:Hydrolases / Q000096:biosynthesis; D007082:Ileum / Q000187:drug effects; D005779:Immunodiffusion; D008854:Microscopy, Electron; D009154:Mutation; D009500:Neutralization Tests; D011817:Rabbits; D013170:Spores; D013171:Spores, Bacterial / Q000254:growth & development; D014118:Toxins, Biological / Q000096:biosynthesis
chemical_list: D003470:Culture Media; D004768:Enterotoxins; D014118:Toxins, Biological; D006867:Hydrolases