# Isolation and characterisation of Klebsiella pneumoniae bacteriophages vB_Kpn_Lilla1 and vB_Kpn_Lilla2

## TL;DR

Researchers isolated two new bacteriophages that can kill Klebsiella pneumoniae, a drug-resistant bacteria, offering a potential alternative treatment.

## Contribution

The discovery and characterization of two novel lytic bacteriophages (vB_Kpn_Lilla1 and vB_Kpn_Lilla2) against Klebsiella species.

## Key findings

- Two new bacteriophages were isolated from wastewater with lytic activity against Klebsiella oxytoca and K. michiganensis.
- Genome analysis placed both phages in the Straboviridae family, with distinct genera Jiaodavirus and Slopekvirus.
- Phage infection effectively reduced Klebsiella pneumoniae populations in growth experiments.

## Abstract

Klebsiella pneumoniae is an opportunistic pathogen that is commonly associated with pulmonary infections. It is of particular concern due to its increasing resistance to antibiotics, particularly carbapenem. Alternative treatments for these bacterial infections are required, and phage application is an attractive option. In this study, we isolated two novel Klebsiella pneumonia bacteriophages from wastewater, vB_Kpn_Lilla1 and vB_Kpn_Lilla2, both of which have lytic activity against Klebsiella oxytoca and Klebsiella michiganensis. Genome sequencing and phylogenetic analysis revealed that both phages belong to the family Straboviridae, with vB_Kpn_Lilla1 belonging to the genus Jiaodavirus and vB_Kpn_Lilla2 belonging to the genus Slopekvirus. Growth kinetics showed an effective reduction of K. pneumoniae populations when infected with either phage.

The online version contains supplementary material available at 10.1007/s00705-025-06374-7.