Horizontal transmission of antimicrobial resistance genes from E. coli to Serratia spp. in minced meat using a gfp tagged plasmid

The transmission of antimicrobial resistance genes from enteric bacteria from the animal reservoir to indigenous bacteria in meat is a serious concern, as it can contribute to human exposure to antimicrobial resistance genes. The aim of this study was to investigate plasmid-mediated horizontal transfer of antimicrobial resistance genes from Escherichia coli to indigenous environmental bacteria in minced pork stored at 10 and 37 °C. E. coli MG1555 containing a gfp-tagged plasmid carrying tetracycline, kanamycin and streptomycin resistance genes was used as the donor with the indigenous bacteria in minced pork acting as potential recipients. The results demonstrated that enteric members of the pork meat microbiota were able to receive gfp-plasmids from the E. coli donor strain at both 10 and 37 °C. The majority of transconjugants were identified as Serratia spp. through sequencing of their 16S rRNA genes. This indicates that environmental Serratia spp. and other Enterobacteriaceae may play a role as carrier of antimicrobial resistance genes through the meat production chain to the consumer.