Isolation and characterisation of pVa-21, a giant bacteriophage with anti-biofilm potential against Vibrio alginolyticus

Abstract

There is an increasing emergence of antibiotic-resistant Vibrio alginolyticus , a zoonotic pathogen that causes mass mortality in aquatic animals and infects humans; therefore, there is a demand for alternatives to antibiotics for the treatment and prevention of infections caused by this pathogen. One possibility is through the exploitation of bacteriophages. In the present study, the novel bacteriophage pVa-21 was classified as Myoviridae and characterised as a candidate biocontrol agent against V. alginolyticus . Its morphology, host range and infectivity, growth characteristics, planktonic or biofilm lytic activity, stability under various conditions, and genome were investigated. Its latent period and burst size were estimated to be approximately 70 min and 58 plaque-forming units/cell, respectively. In addition, phage pVa-21 can inhibit bacterial growth in both the planktonic and biofilm states. Furthermore, phylogenetic and genome analysis revealed that the phage is closely related to the giant phiKZ-like phages and can be classified as a new member of the phiKZ-like bacteriophages that infect bacteria belonging to the family Vibrionaceae .

Strategy for Mass Production of Lytic Staphylococcus Aureus Bacteriophage pSa-3: Contribution of Multiplicity of Infection

“…CFU and serial dilutions of phage solution (10 2 -10 7 PFU/mL) were co-inoculated in fresh LB broth and incubated overnight at 37 °C under shaking conditions (150 rpm). The culture was centrifuged (14,000 × g), ltered (0.45 μm), and puri ed using the PEG precipitation method [41]. A high concentration (~10 10 PFU/mL) of the phage solution was stored at 4 °C for further use.…”

Multisubunit RNA Polymerases of Jumbo Bacteriophages

“…The genome of jumbo phage AR9 infecting B. subtilis , a close relative of the PBS2 phage, was sequenced and shown to contain genes orthologous to the RNAP genes of phiKZ-like phages [ 18 ], suggesting that the PBS2 RNAP purified a long time ago [ 35 , 36 ] in fact belongs to this new group of non-canonical jumbo phage RNAPs. At the time of this writing, several dozens of jumbo phages encoding distant homologs of the β′ and β subunits are known [ 18 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 ]. They infect diverse bacterial hosts including members of Pseudomonas , Salmonella , Yersinia , Erwinia , Vibrio , Ralstonia , Bacillus , Aeromonas , Serratia , Klebsiella , Escherichia , and other genera [ 18 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , …”

A Biological Inventory of Prophages in A. baumannii Genomes Reveal Distinct Distributions in Classes, Length, and Genomic Positions

“…Interestingly, one A. baumannii strain, ACN21, contains a prophage which encodes three antibiotic resistance genes [ aph(3’)-VI , bla NDM – 1 , b l e M B L ]. The phage is most closely related to Vibrio phage pVa-4, a Myovirus that infects V. alginolyticus ( Kim et al, 2019 ). In contrast to its relative, phage pVa-4 is a lytic phage was grouped to be part of the phiKZ-like phages (Phikzviruses), which are considered as “jumbo” phages.…”