[Enterotoxin-producing Bacteroides fragilis strains isolated from horses]

Seven Bacteroides fragilis strains were cultured from samples collected from horses. From all the tested strains, as well as from the reference B. fragilis strains: enterotoxigenic NCTC 11925 and nonenterotoxigenic IPL 323 strain, DNA was isolated using Genomic DNA PREP PLUS isolation kit manufactured by A&A Biotechnology (Poland). To detect the enterotoxin (fragilysin) gene, polymerase chain reaction (PCR) was applied, using the following starters: 404 (GAG CCG AAG ACG GTG TAT GTG ATT TGT) and 407 (TGC TCA GCG CCC AGT ATA TGA CCT AGT). DNA obtained from bacterial cells was amplified in a thermocycler (Techne). The temperature profile was as follows: 1 cycle (4 min. 94 degrees C), 40 cycles (1 min. 94 degrees C, 1 min. 52 degrees C, 1 min. 74 degrees C). Amplification products were detected by electrophoresis in agarose gel (1%) with ethidium bromide added. The presence of the fragilysin gene was detected in two strains. Among the strains isolated from horses enterotoxin gene-possessing Bacteroides fragilis strains (ETBF) can be detected.