Characterization of Bacillus cereus

Bacillus cereus is a ubiquitary microorganism that may cause food borne disease. Pathogenicity, however, depends on various characteristics such as the ability to form (entero)-toxin(s) that can not be detected by microbiological methods. Further characterization of pathogenic properties is not only of importance to identify strains from outbreaks of food borne disease, but also to investigate whether possible pathogenic strains occur on specific types of food. Methods to establish pathogenic properties are described in this report. With a case study the use of the methods as described in this report is clarified. Also the use of methods in research of strains occurring in/on food commodities is discussed. The possibility to discriminate between pathogenic and non-pathogenic B. cereus strains could lead to a re-evaluation of tolerance levels for B. cereus in food commodities. Therefore, further research into the conditions for expression of genes coding for enterotoxins, the way of construction and pathogenic mechanism of enterotoxins is of great importance