Identification of dairy lactic acid bacteria by tRNA(Ala)-23S rDNA-RFLP.

The aim of this study was to evaluate the potential of target tRNAAla–23S ribosomal DNA for identification of lactic acid bacteria strains associated with dairy ecosystem. For this purpose tRNAAla–23S ribosomal DNA Restriction Fragment Length Polymorphism (tRNAAla–23S rDNA-RFLP) was compared with two widely used DNA fingerprinting methods – P1 Random Amplified Polymorphic DNA (RAPD), (GTG)5 repetitive extragenic palindromic PCR (rep-PCR) – for their ability to identify different species on a set of 10 type and 34 reference strains. Moreover, 75 unknown isolates collected during different stages of Grana Padano cheese production and ripening were identified using tRNAAla–23S rDNA-RFLP and compared to the RFLP profiles of the strains in the reference database. This study demonstrated that the target tRNAAla–23S rDNA has high potential in bacterial identification and tRNAAla–23S rDNA-RFLP is a promising method for reliable species-level identification of lactic acid bacteria (LAB) in dairy products.