Emetic toxin producing Bacillus cereus Korean isolates contain genes encoding diarrheal-related enterotoxins

Bacillus cereus can cause the diarrheal and emetic type of food poisoning but the symptoms of emetic food poisoning caused by B. cereus occasionally include emesis and diarrhea. The enterotoxin characteristics of emetic toxin (cereulide) producing B. cereus were needed to be determined. Therefore, forty B. cereus strains isolated from various sources in Korea were investigated for the presence of enterotoxin genes. All strains were confirmed to produce the emetic toxin using HPLC-MS methods. The rates of the nheABC, hblCDA, entFM and cytK genes amongst emetic toxin producing B. cereus strains were 82.5, 7.5, 50.0 and 27.5%, respectively. Pattern III harbored nheABC and entFM genes and pattern V processed entFM gene and were shown to be the major patterns, being present in 55.0% (21 of 40) of the emetic toxin producing B. cereus strains. Our findings revealed that 34 (85.0%) of 40 emetic toxin producing B. cereus strains isolated in Korea have the potential to cause diarrheal and emetic type of food poisoning, simultaneously. Thus, emetic toxin and enterotoxin genes should be constantly screened to provide insight into B. cereus food poisoning.