Medycyna Wet. 64 (7), 906-911, 2008
| Weiner M. |
| Characterization of selected virulence markers of Shiga toxin-producing Escherichia coli originated from raw beef by the use of PCR |
| The aim of the study was the characterization of selected virulence markers of Shiga toxin-producing Escherichia coli originated from raw beef by the use of PCR. The identification of Stx variants (stx2c, stx2d, stx2e and stx2f) was done with the stx2-positive E. coli strains, resulting in the detection of the stx2d gene in 13 STEC isolates out of which 3 strains also had the stx2c gene. None of the isolates possessed the stx2f or stx2e genes. The intimin marker (γ variant) was observed in all E. coli O157:H7, whereas β variant in E. coli O26 isolates. The genotypic factors such as katP, toxB and efa1 were detected in all O157:H7 as well as in one O26 isolate. Fifteen STEC were iha-positive and five saa-positive. None of the saa-positive isolates belonged to the O157 or O26 groups. The simultaneous presence of the lpfAO157/OI-141 and lpfAO157/OI-154 genes was noted in 8 O157:H7 and in one O26 STEC. The lpfAO157/OI-141 gene alone was present in 4 other STEC tested, including one E. coli O26. None of E. coli O157:H7 had the lpfAO113 marker that was observed in the all remaining STEC. In one isolate belonging to the E. coli O26 group, for the first time a simultaneous presence of the lpfAO157/OI-141, lpfAO157/OI-154 and lpfAO113 was noted. |
| Keywords: virulence markers, STEC, PCR, beef |