Genetic diversity of Enterococcus faecium isolated from Bryndza cheese

One hundred and seventy-six Enterococcus faecium isolates from Slovak dairy product Bryndza were tested for the presence of plasmid DNA. Eighty-two isolates were positive and their plasmid DNA was isolated and digested by EcoRI and HindIII restriction endonucleases. The patterns obtained were compared with those obtained after pulsed-field gel electrophoresis of macrorestriction fragments (PFGE), (GTG)5–PCR and ERIC–PCR. All these molecular approaches were applied for the study of genetic variability and determination of strain relatednesses among plasmid-positive isolates of E. faecium. In general, all methods revealed a considerable genetic diversity of E. faecium isolates. Plasmid profiling and ERIC–PCR have offered a higher resolution than PFGE and (GTG)5–PCR.