Isolation and identification of a natural bacteriophage as a biocontrol agent against Proteus vulgaris

Proteus vulgaris as an opportunistic microorganism in
human infections especially in immunodeficient
individuals is of medical importance. While the
potential of bacteriophages as efficient, safe and cost-
effective antimicrobial agents to combat resistant
bacteria was well recognized, lytic phage activity
against P. vulgaris has not been investigated since
1967. Here we describe the isolation and
characterization of a natural lytic phage capable of
infecting P. vulgaris strain, which is isolated from
clinical samples. Following the primary screening, the
most efficient phage was chosen for further
characterization. The morphology, killing efficiency
and bacterial host range were determined under
controlled conditions in the laboratory. Isolated phage
was shown to have broad host range and infected
Bacillus subtilis, Pseudomonas aeruginosa and
Staphylococcus epidermidis as well as P. vulgaris. The
virion was designated as gP0Bh-MGP1 and
characterized by a head diameter of about 84 nm and
a tail size of about 28 × 126 nm. It belongs
morphologically to the myoviridae family as analyzed
by transmission electron microscopy (TEM). Theresult of this investigation indicated that the isolated
phage, gP0Bh-MGP1, is efficient in lysing different
pathogenic agents and may be a good candidate to be
used as an agent to combat infections caused by
resistant strains.