HlyF, an underestimated virulence factor of uropathogenic Escherichia coli

Chagneau, C. V.; Payros, D.; Goman, A.; Goursat, C.; David, L.; Okuno, M.; Bordignon, P.-J.; Seguy, C.; Massip, C.; Branchu, P.; Ogura, Y.; Nougayrede, J.-P.; Marenda, M.; Oswald, E.

doi:10.1101/2023.04.27.538512

bioRxiv · 10.1101/2023.04.27.538512

HlyF, an underestimated virulence factor of uropathogenic Escherichia coli

Chagneau, C. V.·Payros, D.·Goman, A.·Goursat, C.·David, L.·Okuno, M.·Bordignon, P.-J.·Seguy, C.·Massip, C.·Branchu, P.·Ogura, Y.·Nougayrede, J.-P.·Marenda, M.·Oswald, E.

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Abstract

Urinary tract infections (UTIs) are predominantly caused by uropathogenic Escherichia coli (UPEC). By analysing a representative collection of UPEC strains from community-acquired infections, we showed that 20 % of these strains had the ability to produce the protein HlyF. These hlyF+ UPEC strains were the most virulent, mostly responsible for pyelonephritis, often with bloodstream infections. Using a mouse model of UTI, we showed that HlyF was associated with the ability of UPEC to develop a urosepsis, with the presence of bacteria in the spleen and an exacerbated inflammatory response. In contrast to archetypical UPEC strains, hlyF+ UPEC strains are not restricted to phylogroup B2 and harbor a specific repertoire of virulence factors reflecting the fact that HlyF is encoded by conjugative ColV-like plasmids. These plasmids also carry antimicrobial resistance genes, which may facilitate their selection and spreading amongst people receiving antimicrobial therapy. Overall, our data suggest that HlyF is a virulence factor in UPEC and spreading of ColV-like plasmids encoding hlyF warrants further investigation.

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Chagneau, C. V., Payros, D., Goman, A., Goursat, C., David, L., Okuno, M., Bordignon, P.-J., Seguy, C., Massip, C., Branchu, P., Ogura, Y., Nougayrede, J.-P., Marenda, M., Oswald, E.. 2023-04-27. HlyF, an underestimated virulence factor of uropathogenic Escherichia coli. https://doi.org/10.1101/2023.04.27.538512

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