First description of food-borne Salmonella enterica resistance regions R1 and R3 associated with IS26 elements

In this study, we assessed the presence of IS26 in food-borne ASSuT-type Salmonella enterica isolates. A new genetic region (R3) was described, that included a C14 caspase gene between IS26 elements. R3 was present in two Salmonella Rissen isolates from a swine carcass and a meat handler, collected at the same abattoir. Furthermore, a new rearrangement of resistance region R1, harboring the blaTEM-1 gene flanked by IS26 elements, was identified in Salmonella Typhimurium and Salmonella 4,[5],12:i:-, from different samples. This study highlights the zoonotic potential of Salmonella spp. isolates and the possible role of IS26 in the mobilization of resistance genes.