Pseudomonas aeruginosa is a gram negative opportunistic pathogen which is responsible for hospital acquired infections, nosominal infections. Restricted outer-membrane permeability, inactivation of transpeptidation inhibition and antibiotic inactivating enzymes are the primary factors responsible for multidrug resistance in Pseudomonas aeruginosa which has been responsible for increase in morbidity and mortality. Phage Therapy is considered an effective alternative treatment for bacterial infections. Here we report two bacteriophages NRP_PA_S1 and NRP_PA_S2 which were isolated from sewage samples that were collected from Tamil Nadu, India. It produced clear lytic plaques of size 6mm and 5mm. Both the phages exhibited an adsorption time of (15, 10 minutes), short latency period (10, 15 minutes) and a large burst size (132, 254 PFU per infected cell). The phage PA_S1 was very stable at wide temperature range (-20°C to 37 °C), pH (3 to 11.0), UV (10-100 mns), Urea (1-4M) conditions. Phage PNR_PA_S2 was stable at temperature of (0°C to 50°C), pH (3-12), UV(10-30mns), Urea (1-3M). Phages PA_S1 and PA_S2 exhibited moderate host range showing an infectivity rate of 13 and 39% against 51 P.aeruginosa isolates. Based on the results it can be concluded that phage therapy can be an effective strategy to control infections caused by Pseudomonas aeruginosa.

Keywords- Phage therapy, Bacteriophage, Pseudomonas Aeruginosa, Antibiotic Resistance