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Creating Bacterial "Fight Clubs" To Discover New Drugs
Science_afficionado writes: Vanderbilt chemists have shown that creating bacterial 'fight clubs' is an effective way to discover natural biomolecules with the properties required for new drugs. They have demonstrated the method by using it to discover a new class of antibiotic with anti-cancer properties. From the Vanderbilt website: "That is the conclusion of a team of Vanderbilt chemists who have been exploring ways to get bacteria to produce biologically active chemicals which they normally hold in reserve. These compounds are called secondary metabolites. They are designed to protect their bacterial host and attack its enemies, so they often have the right kind of activity to serve as the basis for effective new drugs. In fact, many antibiotics and anticancer compounds in clinical use are either secondary metabolites or their derivatives."
I'm done a little work on phage-based antimicrobials for skin infections.
There are good reasons why phage therapy is largely impractical for medical treatment. The short explanation is that a given 'phage antibiotic' would be effective against only a single species of bacteria and would have to be reformulated every 5 years or so. Testing the safety and efficacy of each of these formulations is costly both in money and time. Under the current US regulatory system, safety and efficacy testing often costs nearly a billion dollars.
The reason why constant reformulation is necessary is that a phage is highly specific to a substrain of bacteria and those bacteria rapidly evolve resistance - faster than they evolve resistance to traditional antibiotics. In nature, phages rapidly evolve alongside their hosts. However, a 'phage antibiotic' has a defined type of phage - and that phage can't be changed without repeating regulatory testing. So after a few years, the bacterial population will have evolved resistance leaving the phage ineffective.
There was a great review paper on phage/host resistance/counter-resistance mechanisms in Nature. I can't find a non-paywalled version, but some of the article is here:
http://www.readcube.com/articles/10.1038%2Fnrmicro2315