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Galyov, E.

Publications and source records attributed to Galyov, E..

3 recordsLinked to original sources

Isolation and characterisation of Lytic Jumbo Klebsiella phage BMPCR_005026

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.

microbiology↗

Rolling out plaque-2-sequence: a single plaque sequencing approach enabling rapid, low-cost sequencing of phages directly from plaques

Rapid, accurate, and scalable sequencing of bacteriophage genomes is critical to advance phage therapy, build phage biobanks and understand phage genomic diversity. Current methods are based on sequencing and assembling complete bacteriophage genomes using short- or long-read technologies. However, current protocols require large DNA input and are cost prohibitive which limits their application to phage collections that typically are large and have low-biomass. In order to address this we have developed plaque-2-sequence, a robust and cost-effective workflow for high-throughput phage genome sequencing that will transform the speed and cost of attaining phage genomes. Plaque-2-sequence combines low-input transposase-based library preparation, amplification, nanopore sequencing and optimised assembly steps tailored to phage genomes. We applied the method to phages isolated on seven genetically diverse bacterial hosts; Escherichia, Pseudomonas, Synechococcus, Enterococcus, Klebsiella , Serratia and Enterobacter. High quality genome assemblies were validated using CheckV and benchmarking against previously sequenced phage isolates. Compared to standard Illumina sequencing, plaque-2-sequence offers [~]10-fold savings in sequencing price for individual labs. Furthermore, it substantially decreases the time required to produce a phage genome, once a plaque is obtained. Offering the ability to routinely obtain hundreds of phage genome sequences a week, with minimal hands-on time. Plaque-2-sequence enables systematic genomic characterisation of phage isolates, facilitating taxonomic classification, for the development of large scale phage biobanks. Impact StatementHere we have optimised a method for high-throughput sequencing of bacteriophage genomes from single plaques (plaque-2-sequence). We present a robust, high-throughput and cost-effective workflow. Plaque-2-sequence combines low-input transposase-based library preparation, amplification, nanopore sequencing and optimised assembly steps tailored to phage genomes. We demonstrate the scalability of this approach by sequencing over 100 phages from multiple bacterial hosts. This marks a step-change for the field, allowing phage genome sequencing to keep pace with phage isolation rates, and transforming how rapidly we can explore and understand phage genomic diversity.

microbiology↗

Phage-induced efflux down-regulation boosts antibiotic efficacy

The interactions between a virus and its host vary in space and time and are affected by the presence of molecules that alter the physiology of either the host or the virus. Determining the molecular mechanisms underpinning these interactions is paramount for predicting the fate of bacterial and phage populations and for designing rational phage-antibiotic therapies. We study the interactions between stationary phase Burkholderia thailandensis and the phage {Phi}Bp-AMP1. Although heterogeneous genetic resistance to phage rapidly emerges in B. thailandensis, the presence of phage enhances the efficacy of three major antibiotic classes, the quinolones, the beta-lactams and the tetracyclines, but antagonizes tetrahydrofolate synthesis inhibitors. We discovered that enhanced antibiotic efficacy is underpinned by reduced antibiotic efflux in the presence of phage. This new phage-antibiotic therapy allows for eradication of stationary phase bacteria, whilst requiring reduced antibiotic concentrations, which is crucial for treating infections in sites where it is difficult to achieve high antibiotic concentrations.

microbiology↗