Characterization of five newly isolated bacteriophages active against Pseudomonas aeruginosa clinical strains

Abstract

Pseudomonas aeruginosa is an opportunistic pathogen that causes serious infections, especially in patients with immunodeficiency. It exhibits multiple mechanisms of resistance, including efflux pumps, antibiotic modifying enzymes and limited membrane permeability. The primary reason for the development of novel therapeutics for P. aeruginosa infections is the declining efficacy of conventional antibiotic therapy. These clinical problems caused a revitalization of interest in bacteriophages, which are highly specific and have very effective antibacterial activity as well as several other advantages over traditional antimicrobial agents. Above all, so far, no serious or irreversible side effects of phage therapy have been described. Five newly purified P. aeruginosa phages named vB_PaeM_WP1, vB_PaeM_WP2, vB_PaeM_WP3, vB_PaeM_WP4 and vB_PaeP_WP5 have been characterized as potential candidates for use in phage therapy. They are representatives of the Myoviridae and Podoviridae families. Their host range, genome size, structural proteins and stability in various physical and chemical conditions were tested. The results of these preliminary investigations indicate that the newly isolated bacteriophages may be considered for use in phagotherapy.

Bacteriophages inhibit biofilms formed by multi-drug resistant bacteria isolated from septic wounds

“…5 μL of 0.5% uranyl acetate was then applied to the grids, and excess solution was immediately removed, and grids were air-dried. Samples were viewed with the FEI Tecnai G2 S-Twin Transmission Electron at an operating voltage at 80 KV (Sangha et al, 2014; Kwiatek et al, 2015; Stalin and Srinivasan, 2016).…”

“…The latent period was defined as the time interval between the adsorption and the beginning of the initial rise in the phage count. The burst size of respective phages was calculated as the ratio of the final phage titer to the initial count of infected bacterial cells during the latent period (Agudelo Suárez et al, 2002; Kwiatek et al, 2015).…”

<p>How Phages Overcome the Challenges of Drug Resistant Bacteria in Clinical Infections</p>

“…[99][100][101] There is even an indication that the phages containing WP1, WP2, WP3, WP4, and WP5 are capable of lysing antibiotic-resistant bacteria, as in the case of MDR and XDR P. aeruginosa. 102 After an in vitro investigation, it was realized that phage ϕkm18p is able to effectively lyse the most XDR A. baumannii and also using of phages as a cocktail has the potential of lysing XDR A. baumannii isolates of all various genotypes. 45 The effect of ϕKMV, ϕPA2, ϕPaer4, and ϕE2005 phages on 11 strains of MDR, and 1 strain of XDR were tested by Abigail and et al The results demonstrated that phages were able to lyse MDR P. aeruginosa and prevent biofilm formation, however, no effect on XDR P. aeruginosa lysis was detected.…”

Bacteriophage Therapy: Developments and Directions

“…pathogens that are currently being targeted for phage therapy. For example, although phage treatments in experimental P. aeruginosa, K. pneumoniae, and A. baumannii infections in animal models have exhibited efficacy [62][63][64][65], phages specific for P. aeruginosa, K. pneumoniae, and A. baumannii have limited host ranges, usually 5%-50% [65][66][67]. Thus, a mix of several phages in a cocktail must be used to cover the diversity of clinically important strains.…”