Identification of the gene encoding a putative tyrosine decarboxylase of Carnobacterium divergens 508. Development of molecular tools for the detection of tyramine-producing bacteria Original Research Article

The gene encoding a putative tyrosine decarboxylase (TyrDC) in Carnobacterium divergens 508 was identified by multiple steps of inverse and conventional PCR. The coding region of the tyrdc gene was 1875 bp in size. A putative tyrosyl-tRNA synthetase gene was identified from a partial gene sequence upstream of the tyrdc gene and another partial ORF potentially coding for an amino acid transporter was identified downstream. Comparison to the TyrDC operon of Enterococcus faecalis showed that these three genes are probably part of an operon involved in tyramine production in C. divergens 508. Homology search allowed for the design of a set of consensual primers in the tyrdc gene. These primers were used in PCR experiments and allowed for the detection of tyramine producing bacteria. In the future, these primers could be used for the early detection of potentially tyramine-forming bacteria in food and beverages.