Enterotoxigenic Profiling of Emetic Toxin- and Enterotoxin-Producing Bacillus cereus, Isolated from Food, Environmental, and Clinical Samples by Multiplex PCR

Bacillus cereus comprises the largest group of endospore-forming bacteria and can cause emetic and diarrheal food poisoning. A total of 496 B. cereus strains isolated from various sources (food, environmental, clinical) were assessed by a multiplex PCR for the presence of enterotoxin genes. The detection rate of nheA, entFM, hblC, and cytK enterotoxin genes among all B. cereus strains was 92.33%, 77.21%, 59.47%, and 47.58%, respectively. Enterotoxigenic profiles were determined in emetic toxin- (8 patterns) and enterotoxin-producing strains (12 patterns). The results provide important information on toxin prevalence and toxigenic profiles of B. cereus from various sources. Our findings revealed that B. cereus must be considered a serious health hazard and Bacillus thuringiensis should be considered of a greater potential concern to food safety among all B. cereus group members. Also, there is need for intensive and continuous monitoring of products embracing both emetic toxin and enterotoxin genes. Practical Application The results show that: (1) the presence of emetic and nonemetic strains in related products should be monitored simultaneously; (2) Bacillus thuringiensis should be considered more seriously as a food hazard; (3) Enterotoxin FM should be considered the 2nd major enterotoxin after nonhemolytic enterotoxin and must therefore be included in any molecular approach used to detect pathogenic B. cereus in food products.