​Isolation and Identification of Novel Staphylococcus Phage as a Novel Therapeutic Agent from Sewage of Livestock Farms

Abstract

Background: Bacteriophages are viruses that infect bacteria. They are obligate intracellular infective agents requiring specific bacterial organism as a host cell for their replication. They are most widely distributed and diverse entities in the biosphere and ubiquitously present in all reservoirs populated by bacterial hosts, such as soil and the intestine of animals. Bacteriophages are very specific in nature selectively replicate in particular bacteria. Methods: In present study we have isolated the bacteriophages from sewage of various livestock farms. Sewage samples (n=150) were collected from different depths of the sewage collection tank from different species viz. cow, buffalo, goat and pig. All the samples were subjected primarily to isolation bacteriophage against S. aureus. Recovered bacteriophages were identified with transmission electron microscopy (TM). Result: Total of twenty seven sewage samples were showing plaque formation by producing lytic activity against S. aureus in double agar overlay method. The recovery percentage of bacteriophages was maximum from cattle farm sewage (30%), followed by buffalo farm sewage (20%) and pig farm sewage (17.50%). The result indicated that recovered Bacteriophage had icosahedral symmetry and head size 52.20 nm with 109 nm tail. Bacteriophage selectively infected S. aureus with a narrow host range. Results indicated that the recovered isolates of bacteriophage remained viable at 50°C for one and two min and no viable survivors were seen at the 5 min exposure. They remained viable at 60°C for 1 min only and did not show viability for 2 and 5 min exposure at 60°C. None of the bacteriophages survived at 70°C for 1, 2 and 5 min. Bacteriophage isolates were completely inactivated below pH 3 and above 11; they remained viable only in pH range of 5 to 9.