36 Tirasak Pasharawipas
treat the particular bacterial infection. It is estimated that each species of
bacterium may be infected by at least 10 phage species (Chibani-Chennoufi,
2004a). Thus, we need to search all the phages, as a cocktail, for particular
specie of bacterial pathogen (Santos et al., 2010). This is like searching for a
needle in a hay stake. However, there is a report of the polyvalent phages
which can infect broad host range of bacteria (Kilic et al., 2001; Lu et al.,
2003). In addition, there is a phage that can orientate its receptor-interacting
gene to synthesize a new molecule for attachment to a different bacterial cell
(Scholl et al., 2001). These information, polyvalent phage and interacting
molecule orientation, can lead to the possibility that we can develop a common
molecule or ligand for phage infection to attack a broad range of bacteria.
Thus, one might propose a study in developing only one kind of phage to treat
more strains or species of bacteria and eliminate the need for various kinds of
phages as a cocktail. To make this successful, we, at least, need to thoroughly
understand the interaction of bacterial cell and phage. This can be very diverse
for each pair of bacteria and phage.
CONCLUSION
One of the advantages of phage treatment is its specificity to pathogenic
bacteria so it cannot cause any harm to normal florae bacteria. However, the
specificity of phage interaction to bacterial cell is also disadvantageous for
phage therapy since it limits the use of phage for treatment to a limited range
of bacterial species. It is more reasonable to use virulent phage more than
temperate phage for bacterial therapy. However, virulent phage is a scarcity
for many bacteria. In this case, the available temperate phages might be an
alternative choice. However, the sufficient amounts of temperate phage must
be administered with special care to prevent the lysogenic infection.
Alternatively, molecular technology can be applied to alter temperate phage to
act as a virulent phage to prevent lysogenic infection. Also, the technology
might produce a phage to attack a broader range strains or even more species
of bacteria. In the future, with our progressive difficulty of using antibiotics,
phage therapy could be an alternative to our fight against bacterial infection
and contamination. In the main of fact, using antibiotics extravagantly by
farmers has been known to be one of the major problems to cause antibiotic
resistance of bacteria. Base on this consideration, it will be better to
decontaminate bacterium with bacteriophage than antibiotic. Although at
present time, there are many obstacles limiting the use of phage therapy for the