Isolation and Characterization of Lytic Coliphages from Sewage Water

Abstract

The goal of this study was to isolate and characterize phages that might be used in transport and treatment of potential E.coli pathogen in water sources. E.coli KP005067 was especially targeted because this is the dominant strain obtained from the sewage canal. The abundance of phage and its host directly from the sewage water was analysed using Epifluorescence Microscopy. The morphological characterization of the bacteriophages was studied using transmission electronic microscopy (TEM) and the genomic studies using Agarose Gel Electrophoresis. Studies on phage growth curve and its survival rate with respect to UV irradiation was also carried out. Almost 64% of the phages produced large, clear plaques indicating lytic activity. Phages had long noncontractile tail and icosahedral capsid head and therefore belonged to the Siphoviridae. Their estimated genome sizes was about 31 kb. One-step growth kinetics of the phage showed the latent period 15 min, rise period 20 min, and the average burst size 35 phage particles/infected cell. Also a clear downward trend in lytic activity was observed in phage groups exposed to longer than 30 minutes of UV. The characterization of the phages will be helpful in its future application as microbial tracers and bio-disinfectants in water sources.

Keywords

• bacteriophage
• sewage
• characterization
• lytic