Characterization of lytic Pseudomonas aeruginosa bacteriophages via biological properties and genomic sequences

Abstract

Pseudomonas aeruginosa is an important cause of infections, especially in patients with immunodeficiency or diabetes. Antibiotics are effective in preventing morbidity and mortality from Pseudomonas infection, but because of spreading multidrug-resistant bacterial strains, bacteriophages are being explored as an alternative therapy. Two newly purified broad host range Pseudomonas phages, named vB_Pae-Kakheti25 and vB_Pae-TbilisiM32, were characterized as candidates for use in phage therapy. Morphology, host range, growth properties, thermal stability, serology, genomic sequence, and virion composition are reported. When phages are used as bactericides, they are used in mixtures to overcome the development of resistance in the targeted bacterial population. These two phages are representative of diverse siphoviral and podoviral phage families, respectively, and hence have unrelated mechanisms of infection and no cross-antigenicity. Composing bactericidal phage mixtures with members of different phage families may decrease the incidence of developing resistance through a common mechanism.

Characterization and genomic study of “phiKMV-Like” phage PAXYB1 infecting Pseudomonas aeruginosa

“…At least 17 protein bands with molecular masses of 6.9–144 kDa were observed. In the previous studies, 12, 13 and 18 proteins from phage phiKMV, LKD16 and M32 were detected, respectively 21,24,28 . To identify as many structural proteins as possible, whole phage PAXYB1 particles were directly digested with trypsin and then detected by mass spectrometry.…”

“…1C). Karumidze’s study showed that the half-lives of P. aeruginosa phages vB_Pae-Kakheti25 and vB_Pae-TbilisiM32 are 49 and 46 min at 70 °C, respectively 21 , which indicates that these two phages are more stable than PAXYB1 at higher temperatures. A survey showed that the titres of P. aeruginosa phages P2S2 and P5U5 decreased following heating for 10 to 50 min at 45 °C or 60 °C 22 .…”

“…It is a Podoviridae from its virion structure, and it has a strong ability to infect several clinical isolates of P. aeruginosa . The genome sequence of this phage is over 90% identical to other members of the PhiKMV-like virus genus 18,20,21 . We also analyzed the particle protein content of this phage and detected 17 structural proteins.…”

Tradeoffs in bacteriophage life histories

“…For example, two lytic Pseudomonas phages were independently isolated from sewage samples and found to have virtually identical host ranges, adsorption rates, and genome sizes but different replication rates; the faster replicator was the more sensitive to thermal inactivation. 20 Such data, though piecemeal, suggest that a higher replication rate is associated with lower phage stability, persistence, and quality. In the microscopic world as much as in the macroscopic world, the benefit of increased survival seems to be balanced against the cost of decreased reproduction.…”

Genome Analysis of Pseudomonas aeruginosa Bacteriophage KPP23, Belonging to the Family Siphoviridae

“…A virulent Pseudomonas phage belonging to the family Siphoviridae is proposed as a therapeutic phage (5). Phage KPP23 was isolated from a water sample collected from Urado Bay, Kochi City, Kochi, Japan, using P. aeruginosa strain PA101 as the host strain (6).…”