Purpose: In this study, (GTG)5 fingerpringting was evaluated for B. sporothermodurans. In addition, the isolation of various strains from UHT milk as well as from the dairy farm were compared using REP PCR and (GTG)5PCR.
Methods: In this report, a collection of 9 B. sporothermodurans strains were obtained from UHT milk or farm sources (i.e. feed concentrate, silage and raw milk) from different countries. These strains were identified using B. sporothermodurans PCR as well as the HRS-PCR method. REP PCR and (GTG)5PCR fingerprinting were performed on all 9 isolates and thereafter analysed using a dendogram.
Results: The two new UHT milk strains (i.e. QA1 from Belgium and F3 from South Africa) were positive for HRS. Four of the 9 isolates from raw milk or feed concentrate were tested negative for HRS. The farm strain MB 1505 sourced from silage was positive for HRS. From the dendogram, B. sporothermodurans strains showed an overall similarity of 40%. The three strains (QA1, F3 and MB 372) showed slight differences in similarity. This would be expected as all the three strains were isolated form UHT milk. It was observed that even though the feed concentrate strains originated from Belgium, the similarity was not more than 80% in both molecular methods.
Significance: (GTG)5 PCR has been used to produce DNA fingerprints for a number of species and in this present study, we showed that this method could be used to fingerprint B. sporothermodurans strains.