Co-occurrence of Plasmid-Mediated Colistin Resistance (mcr-1) and Extended-Spectrum β-Lactamase Encoding Genes in Escherichia coli from Bovine Mastitic Milk in China.

Both mcr-1 phosphoethanolamine transferase enzymes and extended-spectrum β-lactamases (ESBLs) are the main plasmid-mediated mechanisms of resistance to colistin and third-generation cephalosporins,...