Detection of virulence factors, biofilm formation, and biogenic amine production in vancomycin‐resistant lactic acid bacteria (VRLAB) isolated from foods of animal origin

Abstract

The objective of this study was to determine phenotypic and genotypic characteristics of virulence factors, biofilm and biogenic amine production properties of vancomycin-resistant 26 Enterococcus, 18 Pediococcus, and three Weisella strains. The most common virulence genes were observed to be hyl (80.77%, 21/26), ccf (38.46%, 10/26), gelE (30.77%, 8/26), and acm (30.77%, 8/26) in Enterococcus isolates, cylM (44.44%, 8/18) and gelE (33.33%, 6/18) were detected in Pediococcus isolates. Biofilm production was apparent in 97.87% of the investigated isolates. The epaB biofilm formation gene was observed in four Enterococcus isolates, and epaE was identified in one Enterococcus isolate. Tyramine production was detected only in Enterococcus gallinarum DYE22 strain while the tdc gene was also identified in this strain. The results of this study showed that the detection of high-level of virulence genes in VRLAB strains from food of animal origin is a concern for consumer health. Novelty impact statement The most common virulence factor gene in VRLAB strains was found to be hyl. Biofilm production was found to be very common in VRLAB strains. Tyrosine decarboxylation and tdc gene was detected only in one Enterococcus gallinarum strain.