Acid exposure enhances sporulation of certain strains of Clostridium perfringens.

A gastroenteritis results when Clostridium perfringens is ingested in high numbers and sporulates releasing enterotoxin in the intestines. Since the organism must pass through the stomach, its ability to form spores may be affected by the acidic environment. Five strains of C. perfringens were exposed to acidic conditions and then assessed for survival and their ability to form spores. An acidic pH environment kills the bacteria over time but surviving cells are able to recover and form spores. Two of the five strains demonstrated enhanced sporulation following a 30-min exposure to a pH 2 environment. For four of the strains tested, enterotoxin concentrations were higher from acid-exposed cells than from untreated cells. Exposure to a pH 3.5 environment did not affect sporulation when compared to an untreated control. Bacteria in the stationary phase of growth were the most able to resist the acid and sporulate. The results indicate that some strains will produce more spores and enterotoxin following exposure to an acidic environment.