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bioRxiv · 10.1101/2023.09.14.557699

A collection of diverse bacteriophages for biocontrol of ESBL- and AmpC-β-lactamase-producing E. coli

Vitt, A. R.·Sorensen, A. N.·Bojer, M. S.·Bortolaia, V.·Sorensen, M. C. H.·Brondsted, L.
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Abstract

Novel solutions are needed to reduce the risk of transmission of extended spectrum {beta}-lactamase and AmpC {beta}-lactamase producing Escherichia coli (ESBL/AmpC E. coli) in livestock to humans. Since phages are promising biocontrol agents, we established a collection of 28 phages against ESBL/AmpC E. coli and showed by whole genome sequencing that all 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 E. coli, were sensitive to at least one phage. Identifying receptors used for initial binding experimentally as well as in silico predictions, allowed us to combine phages into two different cocktails with broad host range targeting diverse receptors. These phage cocktails inhibit growth and kill ESBL/AmpC E. coli in vitro, thus suggesting the potential of phages as promising biocontrol agents. HIGHLIGHTSO_LI28 unique phages infecting ESBL/AmpC E. coli were isolated and characterized C_LIO_LIBroad host range phages targeting different receptors were used to compose phage cocktails C_LIO_LIPhage cocktails efficiently inhibit growth of ESBL/AmpC E. coli in vitro C_LI

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Vitt, A. R., Sorensen, A. N., Bojer, M. S., Bortolaia, V., Sorensen, M. C. H., Brondsted, L.. 2023-09-14. A collection of diverse bacteriophages for biocontrol of ESBL- and AmpC-β-lactamase-producing E. coli. https://doi.org/10.1101/2023.09.14.557699

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