Tuesday, 13 January 2015

Savior From The Soil: The First New Antibiotic in 30 Years!

Frequent visitors to our little corner of the internet may remember that last April we told a semi-fictional story about antibiotic-resistant bacteria entitled Curious Geoff and the Antibiotic Resistant Superbug. The gist of the story was the true fact that all over the world bacteria are becoming stronger and are better able to resist the drugs we use to treat them. This is a serious problem given that a new antibiotic drug has not been discovered since 1987… until last week anyway.

On January 7, 2015 the journal Nature published an article by a group of researchers reporting the discovery of a new antibiotic. That alone would have been enough to pique the interest of the science and medical communities, but the authors went one step further in the boldness category and called their article “A new antibiotic kills pathogens without detectable resistance.” As boring as that might seem, in the world of medicine it is the equivalent of calling your paper “Tyranosaurus discovered running surf school in rural New Zealand”… Basically no one was expecting it.


The new drug is called Teixobactin and in trials with mice it has been shown to effectively fight staph infections and antibiotic resistant forms of tuberculosis. That is big news given that the usual option for treating the latter is to prescribe drugs you know won’t work and cross your fingers really hard. Better still, the new antibiotic appears to have no side effects and can be given to mice in doses that make it practical for human use. That is, it doesn’t take a barrel of medicine to get them healthy again. Teixobactin works by inhibiting the growth of cell walls by bacteria, giving the immune system a fighting chance against them off.


So how did these researchers do it? How did they break science’s 30 year shut-out streak with regards to developing new antibiotics? Well, it turns out that the method they used might be even more of a breakthrough than the discovery of the drug itself. See, the thing about antibiotics is that the effective ones tend to come from bacteria that live in soil. The trouble is that we humans are pretty terrible at convincing soil bacteria to live and grow in labs. In fact, pretty much every one of our 100 or so antibiotics come from the roughly 1% of bacteria that we can get to grow in petri dishes. That means that 99% of the potentially world-changing drugs that exist in nature have been unavailable to us until last week.


The researchers on the new paper developed a technique that tricks soil bacteria into thinking they are at home when really they are doing our bidding. The approach makes use of what the researchers have termed the iChip, despite Steve Jobs not being listed as an author. It works by suspending bacteria in what basically amount to mini-petri dishes with semi-permeable walls, meaning some things can get in and out. Each iChip contains many of these little bacterial prison cells and is suspended in the type of soil that the bacteria usually thrive in. The result is that the bacteria have access to the nutrients they need to grow, but scientists are still able to isolate the bacteria from the soil for their experiments. This sneaky method of growing bacteria might finally give researchers access to an incredible number of new drugs.


Now, a caveat: this does not mean you can disregard all the advice you’ve been given about antibiotics. Teixobactin may be promising but it is nowhere near the point where you can get it from your local pharmacy. It still has to go through human trials, which could take as long as ten years… but hopefully more like 5. In the meantime, we still can’t afford to prescribe antibiotics willy nilly. Every time a farmer gives a healthy cow antibiotics so it can grow faster, we give up a little bit of our edge. Every time you leave a few pills in the bottle after you start feeling better, we lose some ground in the war on germs.

So remain diligent. Be smart about your use of antibiotics and don’t underestimate the enemy. This new paper may give us some hope and a nifty new trick for developing drugs; but until we truly master the soil, we are at evolution's whim in the fight against resistance.


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