IDENTIFICATION OF CLASSICAL PROPIONIBACTERIUM SPECIES USING 16S RDNA - RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISMS

The phenotypic identification of the classical propionibacteria is ess entially still problematic and alternative techniques for the identifi cation of the various species are required. A rapid and sensitive tech nique for the routine identification of the classical propionibacteria , based on the amplification of the 16S rRNA genes using the polymeras e chain reaction and the subsequent restriction endonuclease digestion of the PCR products, was previously described. Although this techniqu e enabled differentiation between the various classical species examin ed it was only evaluated on a limited number of type and reference str ains. During this study, the taxonomic relationship between 135 Propio nibacterium strains from diverse ecological niches, representing four classical species was investigated using this PCR/RFLP technique. Visu al differentiation between the classical Propionibacterium species was possible after restriction endonuclease digestion of the PCR products obtained using primers 16sP1-16sP4 and 16sP3-16sP4 with the restricti on endonucleases HaeIII, AluI and HpaII, respectively. With the except ion of strains independently identified as ''P. rubrum'' and ''P. sang uineum'', the results of this study confirm the consolidation of the ' 'old'' species into the various classical species as they currently ex ist. It was therefore concluded that the PCR/RFLP protocol is suitable for the rapid and routine identification of the classical propionibac teria.