Phages from Genus Bruynoghevirus and Phage Therapy: Pseudomonas Phage Delta Case.

Petar Knezevic,Jovana Pejic,Gábor Rakhely,Aleksandra Petrovic Fabijan,Damir Gavric,Zsolt Doffkay

doi:10.3390/v13101965

Petar Knezevic, Jovana Pejic + Show 4 more

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https://doi.org/10.3390/v13101965

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Journal: Viruses	Publication Date: Sep 30, 2021
Citations: 4	License type: CC BY 4.0

Affiliation: University of Novi Sad, University of Szeged

Abstract

The applicability and safety of bacteriophage Delta as a potential anti-Pseudomonas aeruginosa agent belonging to genus Bruynoghevirus (family Podoviridae) was characterised. Phage Delta belongs to the species Pseudomonas virus PaP3, which has been described as a temperate, with cos sites at the end of the genome. The phage Delta possesses a genome of 45,970 bp that encodes tRNA for proline (Pro), aspartic acid (Asp) and asparagine (Asn) and does not encode any known protein involved in lysogeny formation or persistence. Analysis showed that phage Delta has 182 bp direct terminal repeats at the end of genome and lysogeny was confirmed, neither upon infection at low nor at high multiplicity of infection (MOI). The turbid plaques that appear on certain host lawns can result from bacteriophage insensitive mutants that occur with higher frequency (10−4). In silico analysis showed that the genome of Delta phage does not encode any known bacterial toxin or virulence factor, determinants of antibiotic resistance and known human allergens. Based on the broad host range and high lytic activity against planktonic and biofilm cells, phage Delta represents a promising candidate for phage therapy.

Highlights

Bacteriophages are potential therapeutic agents against multidrug and pandrug resistant bacteria which are used throughout the world [1]
Three tRNA were detected: tRNA- proline (Pro), asparagine (Asn) and aspartic acid (Asp), as in other strains of Pseudomonas virus PaP3, with an exception of PaP3 phage that encodes tRNA for tyrosine (Tyr) in addition
Analyses of DNA similarity of phage Delta sequence confirmed that this phage belongs to the species Pseudomonas virus Pap3, and that there are nine different strains in total, along with phage Delta, isolated throughout the world that belong to this species (Table 1)

Summary

Introduction

Bacteriophages are potential therapeutic agents against multidrug and pandrug resistant bacteria which are used throughout the world [1]. Temperate phages can integrate their genome into bacterial DNA, and by an imprecise excision during induction (i.e., initiation of a lytic cycle), they can excise bacterial DNA and transfer it into a new bacterial host through specialised transduction [3] Some of these genes can contribute to the virulence or antibiotic resistance of infected bacteria. Sometimes bacterial DNA is packaged into viral particles, and frequency of this phenomenon primarily depends on the DNA packaging mechanism, which is the most prominent in phages that use the head-full mechanism [4] In this context, careful phage selection should prevent the transfer of genes encoding virulence factors, human/animal allergens or genes responsible for bacterial resistance to antibiotics [5,6,7,8]. Some phages encode proteins involved in their own life cycle, which act as eukaryotic toxins or allergens; the best-known example is Vibrio phage

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