Editor: Stefan Schwarz
Determination of the toxic potential of Bacillus cereus isolates by quantitative enterotoxin analyses
Version of Record online: 1 MAR 2006
FEMS Microbiology Letters
Volume 257, Issue 2, pages 293–298, April 2006
How to Cite
Moravek, M., Dietrich, R., Buerk, C., Broussolle, V., Guinebretière, M.-H., Granum, P. E., Nguyen-the, C. and Märtlbauer, E. (2006), Determination of the toxic potential of Bacillus cereus isolates by quantitative enterotoxin analyses. FEMS Microbiology Letters, 257: 293–298. doi: 10.1111/j.1574-6968.2006.00185.x
- Issue online: 1 MAR 2006
- Version of Record online: 1 MAR 2006
- Received 30 November 2005; revised 30 January 2006; accepted 31 January 2006. First published online 1 March 2006.
- Bacillus cereus;
- haemolysin BL (HBL);
- nonhaemolytic enterotoxin (Nhe);
Haemolysin BL (HBL) and nonhaemolytic enterotoxin (Nhe), each consisting of three components, represent the major enterotoxins produced by Bacillus cereus. To evaluate the expression of these toxins, a set of 100 B. cereus strains was examined. Molecular biological characterization showed that 42% of the strains harboured the genes for HBL and 99% for Nhe. The production of all Nhe and HBL components were analyzed using specific antibodies and, in culture supernatants, detectable levels of HBL and Nhe were found for 100% of hbl-positive and 96% of nhe-positive strains. The concentrations of the HBL–L2 and NheB component ranged from 0.02 to 5.6 μg mL−1 and from 0.03 to 14.2 μg mL−1, respectively. Comparison of the amount of NheB produced by food poisoning and food/environmental strains revealed that the median value for all food poisoning strains was significantly higher than for the food/environmental isolates. The data presented in this study provide evidence that specific and quantitative determination of the enterotoxins is necessary to evaluate the toxic potential of B. cereus. In particular, the level of Nhe seems to explain most of the cytotoxic activity of B. cereus isolates and may indicate a highly diarrheic potential.