BACKGROUND: Bacteroides fragilis is a member of normal human flora andwell known pathogenic agent. This bacterium produces many virulence factors. In 1984 new virulence factor--enterotoxinwas described. The aim of the study was to search for enterotoxin gene in B. fragilis strains isolatedfrom clinical specimens.
MATERIAL AND METHODS: Strains isolated in Poland, Great Britain, France andthe Netherlands were cultured on BBE medium. For DNA isolation Genomic DNA PREP PLUS isolation kit manufacturedby A&A Biotechnology (Poland) was used. In order to detect enterotoxin (fragilysin) gene, polymerasechain reaction (PCR) was applied utilizing the following primers: 404 (GAG CGG AAG ACG GTG TAT GTG ATTTGT) and 407 (TGC TCA GCG CCC AGT ATA TGA CCT AGT). DNA obtained from bacterial cells was amplified inthermocycler Techne. The amplification products were detected by the electrophoresis in 1% agarose gel.
RESULTS: Among 65 investigated B. fragilis strains, the enterotoxin gene was detected in DNA isolatedfrom 12 strains.
CONCLUSION: The enterotoxin producing B. fragilis strains were detected among strainsisolated from different clinical specimens in Poland, Great Britain, the Netherlands and France.

Keywords: Bacteroides fragilis, enterotoxin fragilysine, enterotoxin fragilysine