Bacteriophages have been found to be effective against
a wide variety of pathogenic bacteria as they are highly host specific.
The present study describes the isolation of bacteriophages effective
against few human pathogens such as Salmonella typhi, Escherichia
coli andPseudomonas aeruginosa. A total of five isolates of
bacteria were obtained from the sewage water, sampled from the sewage
treatment plant located at Jinke Park, Bangalore, India. Based upon the
colony morphology, biochemical characterization and growth on selective
media, the isolates were identified as Escherichia coli, Salmonella
typhi, Pseudomonas aeruginosa, Klebsiella species and
Shigella species. Out of the five different isolates three were
sensitive to bacteriophages. The sensitive cultures belonged to the genera
Salmonella typhi,Escherichia coli andPseudomonas aeruginosa.
The phage filtrates, when spotted onto the lawn cultures of the respective
host bacterium, resulted in the development of clear zones indicating
the presence of lytic bacteriophages against the host bacteria. It was
also found that each of the phages for E. coli and Salmonella
typhi was only able to infect its original host bacterium, whereas,
the phage for Pseudomonas aeruginosa was able to infect both
Pseudomonas and E. coli. Studies of the morphology and characterization
of these phages are currently being conducted. These isolated phages may
hold a lot of promise as the first choice of prophylaxis (Phage Therapy)
against nosocomial and secondary infections by deadly multi-drug resistant
bacteria in the near future.
Mahadevan M. Sundar, Nagananda G.S., Arijit Das, Sourav Bhattacharya and Sandeep Suryan, 2009. Isolation of Host-Specific Bacteriophages from Sewage Against Human Pathogens. Asian Journal of Biotechnology, 1: 163-170.