gram-positive anaerobic spore-formers.

C. botulinum: botulism.
C. difficile: antibiotic-associated diarrhea, antibiotic-associated pseudomembranous colitis.
C. perfingens: food poisoning, gas gangrene (clostridial myonecrosis), enteritis necroticans.
C. tetani: tetanus.

Bacteria; Firmicutes; Clostridia; Eubacteriales; Clostridiaceae; Clostridium