The genus Clostridium contains a variety of anaerobic, gram positive spore-forming bacilli. The natural habitat is the soil and intestinal tracts of Man and animals.
It includes the following species:
Classification is due primarily to differential sugar fermentation tests and by the morphology of sporangium. Generally, pathogenicity is dependent on the release of very destructive enzymes or exotoxins.
Clostridia are sensitive to penicillin and metronidazole.