First Steps Towards the Latvian Klebsiella spp. Bacteriophage Biobank

Description

Objectives
Bacterial genus Klebsiella representatives are often implicated in healthcare-associated infections of otherwise compromised patients. While drug-resistant K. pneumoniae strains are widely regarded as the main Klebsiella spp. isolates of concern, the genus also hosts other species of relevance, such as K.oxytoca. Deliberate use of bacteriophages to treat bacterial infections - phage therapy seems a prospective alternative strategy to treat extensively drug-resistant bacteria and is experiencing a renaissance (either as a standalone treatment or in combination with antibiotics). To increase the possibility of phage therapy application in Latvia, our team attempts to accumulate a collection of strictly lytic bacteriophages infecting epidemiologically relevant Klebsiella spp. strains prevalent in Latvia.

Materials and Methods
Bacterial strains isolated from patients infected by drug-resistant Klebsiella spp., as well as "healthcare-environment" strains from hospital sewage are used as the isolation hosts to obtain novel tailed bacteriophages. These bacteriophages get propagated and subjected to whole-genome sequencing. Strictly lytic bacteriophages not encoding any known proteins that would preclude their practical use (e.g., virulence factors, AMR genes) get characterized in terms of their host range and lifecycle characteristics, and proceed to long-term storage as potential candidates for therapeutic use.

Results
The "sequencing first" workflow using randomly requested drug-resistant bacterial strains has resulted in a frequent recovery of very similar bacteriophages with little value added regarding the effective phage diversity of our emergent collection. This has prompted a greater focus on the informed diversification of the isolation host panel (selecting relevant isolation strains based on their WGS data, e.g., different ST and KL types).

Conclusions
Shifting our focus on the Klebsiella spp. strains most prevalent locally (e.g., K. pneumoniae sequence types 147, 512, 215, 219) has resulted in the isolation of a wider diversity of relevant bacteriophages. Characterization of target bacterial pathogen diversity is as important as the characterization of novel phage candidates for phage therapy.

Period	26 Mar 2025
Event title	RSU Research Week 2025: Knowledge for Use in Practice
Event type	Conference
Organiser	Rīga Stradiņš University
Location	Riga, LatviaShow on map
Degree of Recognition	International