
Full text loading...
Category: Food Microbiology
Bacillus cereus, Page 1 of 2
< Previous page | Next page > /docserver/preview/fulltext/10.1128/9781555819972/9781555819965.ch20-1.gif /docserver/preview/fulltext/10.1128/9781555819972/9781555819965.ch20-2.gifAbstract:
The Bacillus cereus group currently consists of nine Bacillus species, i.e., B. anthracis, B. cereus, B. mycoides, B. pseudomycoides, B. thuringiensis, B. weihenstephanensis, B. cytotoxicus, B. bombysepticus, and the most recent member of the group, B. toyonensis. The species within the B. cereus group are very closely related, and their toxicity ranges from avirulent strains used as probiotics to highly toxic strains responsible for severe illness and fatalities. B. cereus causes two different types of foodborne illness: the diarrheal type caused by enterotoxins and the emetic type caused by a small heat-stable emetic toxin. For both these types of foodborne illness, the food involved has usually been heat treated, and surviving spores are the source of the food poisoning. The members of the B. cereus group are common soil saprophytes and are easily spread to many types of foods, especially those of plant origin (rice and pasta), but are also frequently isolated from dairy products. Some strains of the B. cereus group are able to grow at refrigeration temperature. These variants raise concerns regarding the safety of cooked, refrigerated foods with extended shelf lives. Foodborne B. cereus illness is probably greatly underreported, as both types of illness are usually mild and last for less than 24 hours. However, more severe forms of B. cereus foodborne illness, including fatalities, are reported occasionally.
Full text loading...
Types of foods involved in B. cereus food poisoning in Europe (European Food Safety Authority) ( 46 ).
Schematic overview of the promoter regions of the three major enterotoxin operons in B. cereus sensu lato ( 109 ). The −35 and −10 regions and transcriptional start sites (bent arrows) ( 78 , 92 , 117 , 118 ), CodY binding sites ( 109 ), catabolite-responsive element (Cre) ( 103 ), PlcR binding sites ( 78 , 92 , 93 , 117 ), SinR binding sites ( 105 , 106 ), and ribosomal binding sites (RBS) are indicated. The inverted repeat possibly involved in regulation of translation of nheC is indicated between nheB and nheC ( 78 ).
Criteria to differentiate members of the B. cereus group a
Examples of foods involved in B. cereus food poisoning events
Characteristics of the two types of illness caused by B. cereus a
Properties of the B. cereus emetic toxin cereulide a
Toxins produced by B. cereus
Properties of the Nhe proteins a