Identification of a gene encoding a putative phosphotransferase system enzyme IIBC in Listeria welshimeri and its application for diagnostic PCR

AIMS: To identify a Listeria welshimeri-specific gene that can be used for identification of this species by PCR. METHODS AND RESULTS: Through comparative analysis of genomic DNA from Listeria species using dot blot hybridization, an L. welshimeri-specific clone was isolated that contained a gene segment whose translated protein sequence is similar to enzyme IIBC from phosphotransferase systems in other bacteria. Using oligonucleotide primers derived from this L. welshimeri-specific clone, a 608-bp fragment was amplified from L. welshimeri genomic DNA and not from other Listeria species or other Gram-negative and Gram-positive species. CONCLUSION AND SIGNIFICANCE: The PCR employing L. welshimeri-specific primers shows promise as a useful method for differentiating L. welshimeri from other Listeria species and related bacteria.