Field of Science

Phages this is my first post, I might as well start with what I'm working on. Bacteriophages.

Bacteriophages (usually shortened to phages) are viruses that attack bacteria. They tend to look like little lunar landing modules; essentially they 'land' on the bacteria, inject in their DNA and replicate it using the bacterial DNA replication proteins. They propagate inside the bacterial cell and then, when finished, burst out of it. This kills the bacteria and leads eventually to nice little plaques forming on an agar plate.

The most interesting thing about phages is that they attack bacteria exclusively. This is because bacteria are prokaryotic, and have a very different internal structure too eukaryote cells (like yours, or mine, or that of a sheep etc). Prokaryotes have no nucleus, and no proper chromosomes, usually just circular loops of DNA. They also use different types of replication proteins and have very different cell surface proteins (although some bacteria can mimic host cell proteins, mostly for infection purposes).

This means that the best thing about phages is that they can potentially be used to treat bacterial infections. Once the phages reach the site of infection they can multiply, kill off the bacteria, and then quietly depart (I am still not exactly sure what actually happens to phages once they've killed all the bacteria, but what I do know is that they are not dangerous in any way). This is a wonderful idea, saves the use of antibiotics, but also carries a slight social stigma with it, after all technically it involves giving people viruses. Even though these viruses don't actually do people any harm at all.

Then I read this:

For those unwilling to trawl through the link, the basic information is that not only is phage theory a good idea in practise, it is also an idea that works. While Western Europe has been fiddling around with antibiotics and coping with MRSA and other resistant bugs, there are labs in Eastern Europe that are already researching and testing phage therapy. They have very small labs and the conditions and funding are both fairly appaling but the work is being done. This, I think, was my favourite sentance:

"Each soldier in the Georgian army carried a spray-on phage cocktail which they used to disinfect their wounds "

The stuff is actually out there, it works and it's relatively safe (more on that in a bit), why isn't it being researched and tried more often?

There are very few side affects associated with phage therapy. As far as I know there's really only one although it is potentially fairly hazerdous. Phages work by killing the bacteria (as mentioned before) which unfortunately leaves a large amount of bacterial debris. In some cases, this is picked up on by the immune system which assumes it's under massive bacterial invasion and over-reacts. This produces what's known as a 'cytokine storm' where lots of immune chemicals (e.g cytokines) are released causing a result similar to anaphalaxis (which is what happens with asthma and allergic reactions).

This is not, however, a novel side effect. It already happens with some antibiotics. And phage therapy has so many more benefits. Bacterial resistance happens less often, and as the phages mainly use the virulence factor surface proteins (the proteins which produce the things that make you feel ill) of bacteria as markers for landing and invasion, resistant strains will be less dangerous. Phages can also evolve with the bacteria, changing to adapt to resistant mutants.

That's why I decided to work on phage therapy.

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