Identification of a New Tetracycline Resistance Determinant tet47 from Fish Intestine

To better understand food safety risks, functional genomic analysis was conducted to identify undescribed antibiotic resistance genes in fish samples from an aquaculture fish farm in Ohio. A fosmid genomic library from pooled DNA of antibiotic-resistant isolates was used to screen for resistance genes against tetracycline (Tet). A new Tet-resistant determinant designated as tet 47 was identified, with the original hosts being Providencia spp. from fish intestine. The new gene was also found to confer Tet resistance in Escherichia coli. Fish and byproducts were shown to be possible carriers that may disseminate new, functional, and potentially transmissible antibiotic resistance determinants through food, feed, and environmental contacts.