Diverse bacteriophages for biocontrol of ESBL- and AmpC-β-lactamase-producing E. coli

Abstract

Novel solutions are needed to reduce the risk of transmission of extended spectrum β-lactamase (ESBL) and AmpC β-lactamase producing <i>Escherichia coli</i> (ESBL/AmpC <i>E. coli</i>) from livestock to humans. Given that phages are promising biocontrol agents, a collection of 28 phages that infect ESBL/AmpC <i>E. coli</i> were established. Whole genome sequencing showed that all these phages were unique and could be assigned to 15 different genera. Host range analysis showed that 82% of 198 strains, representing the genetic diversity of ESBL/AmpC <i>E. coli</i>, were sensitive to at least one phage. Identifying receptors used for phage binding experimentally as well as <i>in silico</i> predictions, allowed us to combine phages into two different cocktails with broad host range targeting diverse receptors. These phage cocktails efficiently inhibit the growth of ESBL/AmpC <i>E. coli in vitro</i>, thus suggesting the potential of phages as promising biocontrol agents.