Exotoxin, food poisoning

Bacillus cereus exotoxin is produced in the gastrointestinal tract after ingestion of improperly stored boiled or fried rice. B. cereus toxin is thermoresistant, as is staphylococcal enterotoxin. Symptoms of food poisoning occur up to six hours after food ingestion and are not characteristic (Butterton and Claderwood, 2001). 

A. Characteristics. Staphylococcal Enterotoxin B (SEB) is one of several exotoxins produced by Staphylococcus aureus, causing food poisoning when ingested. A BW attack with aerosol delivery of SEB to the respiratory tract produces a distinct syndrome causing significant morbidity and potential mortality. 

Enterotoxins. Toxic proteins formed by bacteria with molecular masses in the range from 27000 to 30000 which are usually excreted into the medium ( exotoxins). E. can be taken up with contaminated food or be formed by the bacteria colonizing the intestinal walls. Finally, the bacteria can penetrate the intestinal walls and then start to excrete the E. Some E. are thermally very stable and survive when food is boiled. E. from Salmonella and Staphylococcus species are the most frequent causes of food poisoning. Shortly after uptake, the symptoms of nausea, vomiting, diarrhea, and circulatory complaints occur. Deaths are rare and occur only when the subject is already in a weakened state. The sites of attack by E. vary, e.g., at intestinal epithelial cells or in the vegetative nervous system. For the production of antitoxins, E. are obtained by lysis of bacterial cells or from cell-free culture filtrates. E. have been detected, e. g., in the following bacterial species Bacillus cereus, Clostridium perfringens, Escherichia coli. Vibrio cholerae. Staphylococcus aureus, and Streptococcus faecalis. 

Disease syndromes caused by ingestion of endotoxin or exotoxin from food, by bacteria that produce poisonous substances in a patient s gastrointestinal system, and by xenobiotics present in food products, are a major challenge for medical personnel. 

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