Correlation between cytotoxin production and sporulation in Clostridium difficile.

Correlation between cytotoxin production and sporulation was demonstrated when a Clostridium difficile culture was inoculated into fresh broth to give an initial count of less than 10 vegetative cells/ml with no spores. Under these conditions, cytotoxin was produced and released during sporulation. Addition of a sporulation inhibitor (acridine orange, 30 mg/L), resulted in a marked decrease in both sporulation and cytotoxin production, despite there being no change in the number of vegetative cells in the culture. These results indicate that sporulation might be closely related to cytotoxin production.