Temperate Bacteriophages (Prophages) inPseudomonas aeruginosaIsolates Belonging to the International Cystic Fibrosis Clone (CC274)

Abstract

Bacteriophages are important in bacterial ecology and evolution.Pseudomonas aeruginosais the most prevalent bacterial pathogen in chronic bronchopulmonary infection in cystic fibrosis (CF). In this study, we used bioinformatics, microbiological and microscopy techniques to analyze the bacteriophages present in 24P. aeruginosaisolates belonging to the international CF clone (ST274-CC274). Interestingly, we detected the presence of five members of theInoviridaefamily of prophages (Pf1, Pf4, Pf5, Pf6, Pf7), which have previously been observed inP. aeruginosa. In addition, we identified a new filamentous prophage, designated Pf8, in theP. aeruginosaAUS411.500 isolate belonging to the international CF clone. We detected only one prophage, never previously described, from the familySiphoviridiae(with 66 proteins and displaying homology with PHAGE_Pseudo_phi297_NC_016762). This prophage was isolated from theP. aeruginosaAUS531 isolate carrying a new gene which is implicated in the phage infection ability, named Bacteriophage Control Infection (bci). We characterized the role of the Bci protein in bacteriophage infection and in regulating the host Quorum Sensing (QS) system, motility and biofilm and pyocyanin production in theP. aeruginosaisogenic mutant AUS531 Delta bciisolate. The findings may be relevant for the identification of targets in the development of new strategies to controlP. aeruginosainfections, particularly in CF patients.