Bacteriophages, killing harmful bacteria (Kirby and Barr, 2013). Regardless

Bacteriophages, without
doubt, play a key role in the study of biology and ecosystems, but they are
still hardly understood (Kirby and Barr, 2013). In the 1950s, the Hershey-Chase
experiments utilized phages to better understand the role of DNA in biology,
and as a result, opened the field to new research opportunities and unanswered
questions.  The more research done on
phages, the more apparent it becomes how mysterious and unique phages are. They
are powerful in that they collectively influence ecosystems dramatically by
altering the DNA of bacteria (Kirby and Barr, 2013). Upon closer look at the
relationships between aphids and symbiotic bacteria, phages have been found to
play a part in their interactions. They may in fact be tripartite relationships.
For example, bacteria present in pea aphids can become infected with a phage
that encodes a toxin which protects the aphid from parasitic wasps (Kirby and
Barr, 2013). Many unseen interactions between bacteria and phages like this
contribute to the overall conclusion that the molecular biology of large
organisms depends upon much smaller entities. Phages move from one host to the
next, altering the genome as they go, and changing ecosystems (Kirby and Barr,
2013).  Viruses are popularly thought to
be inherently harmful to people, which makes sense because they often make
their hosts sick. Roughly 100 years ago however, Felix d’Herelle discovered
that viruses can be good too. Since they are so aimed and target specific
bacteria, it’s possible to find the phages that destroy the bacteria that is
harming a patient and introduce it to their system. A way of finding the phages
needed is directly from the harmful bacteria (Kirby and Barr, 2013). Phages are
very adaptive and their behavior is majorly unpredictable. They can change the
host cell’s DNA instead of killing it to preserve its own DNA for future
replication. The unpredictable nature of phages causes phage therapy to have a high
risk-factor. It’s unclear which phages may later cause disease instead of
killing harmful bacteria (Kirby and Barr, 2013). Regardless of the high risk,
the usefulness of phage therapy has been apparent, as other countries have used
it across Europe. The US FDA banned the use of phage therapy, due to uncertain
outcomes. Still, even though there is little interest in phage research, there
are some products using phages in development (Kirby and Barr, 2013). The use
of phages in bacteria control in the US Food Industry, veterinary medicine, and
commercial agriculture however, is growing. In agriculture for example, there
are phage-based sprays that are being used in conjunction with pesticides to
kill bacteria that infect plants and crops (Kirby and Barr, 2013). Phages and
their hosts, bacteria, are constantly battling for survival, which leads to
rapid evolution on both ends. There are approximately 2.5 x 1022
altered viruses every second. This makes them nearly impossible to control and
hard to study. Still, the potential of phages is great due to their ability to
stay relatively stable genetically yet change and affect ecosystems so
dramatically. Overall, phages have immeasurable potential and further research
will almost definitively lead to great advancements in all biological fields (Kirby
and Barr, 2013).