Phage Therapy- A Modifiable Resolution to Combat Resistant Bacteria

Objectives: Not long ago, antibiotics were considered to be wonder drugs against deadly diseases. Because they worked so well, they have been used too often worldwide. The result was the rise of untreatable bacteria that are multidrug resistant. A promising alternative approach is bacteriophage (phage) therapy. Phages play a key role in the natural balance in a predator-prey relationship with bacteria and thus have the potential to be efficient anti-bacterial agents.
Moreover, phage therapy may be advantageous against resistant bacteria. Previously we isolated an efficient phage against Enterococcus faecalis termed EFDG1. As part of a natural evolution course, resistant bacteria to our EFDG1 emerged (termed as resistant EF_EFDG1). Herein we show that a new phage against the resistant strain can be rapidly and easily isolated.
Methods: EFLK1 was isolated from the environment. The new phage was visualized using scanning electron microscopy, characterized by whole genome sequencing, its efficacy against bacterial strains was determined, and the toxicity to cells was measured with XTT.
Results: An EFDG1 strain termed resistant-EF_EFDG1 was isolated from E. faecalis infected culture. A newly isolated phage, EFLK1, which showed an effective lytic activity against resistant-EF_EFDG1 planktonic cultures as well as biofilms, was isolated. Genome sequencing showed that EFLK1, as well as EFDG1 belong to the Spounavirinae subfamily of the Myoviridae phages and they share similarity of about 30%. Viability indicator showed that both EFDG1 and EFLK1 are not toxic to cells.
Conclusions: In conclusion, at least in this case, phage therapy is advantageous over antibiotics when resistant bacteria emerge, due to the simplicity of phage isolation and modification.