Characterization of Pseudomonas aeruginosa PAO Specific Bacteriophages Isolated from Sewage Samples

The purpose of this study was to isolate and characterize Pseudomonas aeruginosa phages with regard to their morphology, growth characteristics, genetic material and structural protein composition. Five phages specific to P. aeruginosa PAO were isolated from sewage samples. Adsorption rates and one step growth curves of these phages were determined and on this basis, phages were found to be distinct entities. DNA of all the phages subjected to restriction enzyme digestion, confirmed the presence of double stranded (ds) DNA as well as heterogeneity among these phages. RAPD PCR analysis of the phage DNA also revealed difference among all the 5 phages as distinct banding patterns were seen in each case. Transmission electron microscopy (TEM) however, showed morphological similarity among the phages as all were assigned to family Podoviridae, order Caudovirales on the basis of their head and tail morphologies, with some size variations. Earlier reports revealed that Pseudomonas phages either belonged to family Siphoviridae, Myoviridae or Podoviridae. However, in the present study, we report isolation of P. aeruginosa phages belonging to family Podoviridae with icosahederal heads and short stumpy non-contractile tails first time