Bacillus cereus: Pathogenicity, Viability and Adaptation

Abstract

Bacillus cereus (B. cereus) is a motile spore-forming Gram-positive bacterium. The endospores are broadly oval-shaped or sometimes cylindrical or round and are resistant to unsuitable conditions. The bacterium is a natural inhabitant in soil and has frequently been detected in various foods. Food contamination may occur during processing as B. cereus spores have strong adhesion properties through their biofilm formation. Two main types of an intestinal illness named emetic (vomiting) and diarrhea are caused by B. cereus. Moreover, the bacterium causes several systemic and local infections in both immunocompromised and immunocompetent individuals. These include fulminant sepsis, progressive pneumonia-like anthrax, and devastating infections of the central nervous system. The pathogenicity is intimately associated with tissue-destructive exo-enzymes production, such as hemolysins, phospholipases, proteases and the emetic toxin. B. cereus growth could be inhibited by high temperature (> 105°C) and canning and storage below 4°C. However, exposure of B. cereus to different stresses might result in an enhanced thermo-tolerance. We reviewed virulence attributes, pathogenesis of B. cereus, viability, and adaptation of this particular bacterium.