Isolation and characterisation of Lytic Jumbo Klebsiella phage BMPCR_005026

Lloyd-Evans, I.; Ford, M.; Hazzard, J.; Bartis, C.; Patel, F.; Roemer, N.; Wright, K.; Porter, K.; Coleman, M.; Galyov, E.; Megremis, S.; Clokie, M. R.; Millard, A. D.; Michniewski, S.; Wilkinson, R. C.

doi:10.64898/2026.09.30.755614

bioRxiv · 10.64898/2026.09.30.755614

Isolation and characterisation of Lytic Jumbo Klebsiella phage BMPCR_005026

Lloyd-Evans, I.·Ford, M.·Hazzard, J.·Bartis, C.·Patel, F.·Roemer, N.·Wright, K.·Porter, K.·Coleman, M.·Galyov, E.·Megremis, S.·Clokie, M. R.·Millard, A. D.·Michniewski, S.·Wilkinson, R. C.

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Abstract

Background: Klebsiella pneumoniae is a key causative agent of multidrug resistant nosocomial infections. Bacteriophages offer a promising alternative treatment, but the diversity of Klebsiella species requires the characterisation of a broad range of phages, particularly the poorly characterised jumbo phages. Materials and Methods: Phage BMCPR_005026 was isolated from sewage against Klebsiella pneumoniae. Whole genome sequencing, transmission electron microscopy and host range analysis against a diverse set of 40 clinically relevant Klebsiella strains were used to characterise the phage. Results: The virion had a myovirus morphology and genomic analysis placed it within an undefined family in Caudoviricetes where it forms a new species within the genus Alcyoneusvirus. BMCPR_005026 could form plaques on 3 of the 40 Klebsiella strains tested (7.5%) and formed halos. Conclusion: BMCPR_005026 represents a new species of phage within the genus Alcyoneusvirus with activity against 3 Klebsiella KL-types.

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Lloyd-Evans, I., Ford, M., Hazzard, J., Bartis, C., Patel, F., Roemer, N., Wright, K., Porter, K., Coleman, M., Galyov, E., Megremis, S., Clokie, M. R., Millard, A. D., Michniewski, S., Wilkinson, R. C.. 2026-10-01. Isolation and characterisation of Lytic Jumbo Klebsiella phage BMPCR_005026. https://doi.org/10.64898/2026.09.30.755614

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