Background: The use of
bacterial viruses has become of major interest in treatment of multi drug
pathogens such as klebsiella pneumoniae. We studied the
susceptibility of klebsiella pneumoniae to a mixture of two lytic
bacteriophages isolated from a hospital waste water treatment plant.
Methods: Phage isolation was carried out by taking
samples from the outlets of three hospital wastewater treatment plants. The
samples were filtered using 0.45?m filters after centrifugation at 6,000rpm,
10min. An overnight culture of Klebsiella pneumoniae ATCC 10031 (volume
5ml) was mixed with
1ml Volume of the filtered water samples and incubated for 24h at 370C
before centrifugation at 6000Rpm and
filtering through a 0.22?m membrane filter. Titration of the lytic phages in
the filtrates was examined by the double layer method using 100µl of
the diluted virus with 400µl of the ATCC strain (0.5 McFarland) in 5ml of 0.75%
molten soft agar before layering the mixture on nutrient agar plates. The
plates were incubated at 37°C overnight and the resulting plaque forming units
(PFU) were then counted. The phage mixture was then centrifuged at 6000rpm and
the pellet was washed using ammonium acetate (0.1 M, pH 7.0). A portion of the
resuspended sediment was deposited on formvar carbon coated grid Cu Mesh 300,
stained with 2% uranyl acetate and examined in EM10C (Zeiss, Germany) transmission
electron microscope at 100kV.
Results: Two lytic bacteriophages were isolated which
formed 1 and 2 mm plaques when plated against the klebsiella pneumoniae
host strain. The TEM results showed that the isolated phases resembled the
tailed bacteriophages of Siphoviridae and Myoviridae families.
Conclusions: The bacteriophages isolated in this research
showed specificity towards klebsiella pneumoniae ATCC host
strain. Further research is underway to examine their potential use against
multi drug resistant klebsiella pneumoniae.