Saturday, April 23, 2016

T Is For Teixobactin: The Dirt On Dirt's New Gift To Man #AtoZChallenge

Methicillin- resistant staphylococcus aureus (MRSA)
Dirt is a battlefield. It contains a wealth of life, much of it engaged in a constant battle to exist. Microorganisms which dwell in the soil around us often secrete antimicrobial compounds; one of these has finally provided us with hope in the fight against current drug-resistant bacteria such as MRSA.

The first classes of antibiotics were the sulfonamides (1935) and the penicillins (1941). The last class introduced were the lipopeptides (2003). As you no doubt already know, efficacy of many antibiotics has been compromised by over-prescribing, the unrestricted sale over-the-counter in many countries, and their prolific use in the agricultural community. Drug-resistant infections are on the rise, as are the number of deaths from agents such as MRSA and MDR-TB (multi-drug resistant tuberculosis).

Enter Kim Lewis and her team at Northeastern University in Boston. Because 99% of  microbes are impossible to culture in labs, they had to find a way to isolate microbes on the bugs' home turf in order to test their potential for life-saving compounds that we might add to our drug arsenal.

Lewis' team created and patented something called the iChip (now licensed to NovoBiotic Pharmaceuticals) which allows testing of organisms in the soil. After screening some 10,000 bacteria samples, they discovered a new bacteria, Eleftheria terrae, which secretes a compound called Teixobactin . Teixobactin is exciting because in mammal cell and mouse tests, Teixobactin managed to kill many of the "superbugs" which have bedeviled medicine of late including MRSA, C. Difficile and drug resistant strains of TB.

The bad news is that it may take anywhere from 5-10 years for human trials to be fully completed and Teixobactin to hit the market. And while Teixobactin is also being cautiously touted as "resistant to resistance", history has unfortunately proven that bacteria are fiendishly clever when it comes to surviving. Therefore we will need to continue digging in the dirt for new classes of antibiotics - and thanks to the iChip, we now have a better way to do so.


Lewis K, et. al. Nature (January 22, 2015) "A New Antibiotic Kills Pathogens Without Detectable Resistance "

Mohan G, LA Times (January 7, 2015) "New Antibiotic Teixobactin Kills Drug-Resistant Superbugs, Study Says  Retrieved February 13, 2016

7 comments:

  1. This is interesting news as my husband caught both those superbugs while in a local hospital here and much of the reason was the slack cleanliness standards of the nurses who kept spreading the germs because of lack of thoroughness and nurses who felt cleaning up the patient wasn't their job . . . MRSA and C. Difficule (or C. Diff). spread quickly. I spent many hours by hubs side when he had these infections and had to clean his bed rails, fingernails, etc. It took 6 months of work after he came home and a dermatologist to get rid of the MRSA. Hubs still has scars on his back. . .this is good news but sad that it may take so long to get it available for those who need it.

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    1. Wow, I'm sorry you had to go through that! I'm terrified of hospitals for precisely that reason. If I visit someone, I usually scrub my hands at every chance, wipe things down, then go home and shower, launder my clothes - I even wipe the bottoms of my shoes with Lysol or Clorox bleach.

      Hopefully they can speed things up and get it to market sooner than 10 years. Of course, the other problem will probably cost when/if it does hit the market.

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  2. This was fascinating! And to think that dirt would hold the answer:-)

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    1. I thought the same thing! I always think of dirt as containing nothing but "bad" things like anthrax and whatever causes tetanus. But it makes sense that there would be other agents designed to combat those. Nature is truly balanced - and marvelous.

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  3. How interesting. I know there are increasing warnings about the efficacy of antibiotics, so whilst this may take a while, it could be a life saver for future generations.

    Susan A Eames from
    Travel, Fiction and Photos

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    1. I fear that we will be in serious trouble very soon. Mankind has squandered a valuable resource by doctors handing out antibiotics willy-nilly, patients not following directions and completing the dosage course, farmers dumping them into animal feed, etc. If we don't find new ones soon, many pathogens will have built up immunity to what we have and more and more infections will be untreatable - and lethal.

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  4. I'm a bit cynical - as you pointed out bacteria are fiendishly clever and they keep mutating and evolving, in the same way that using roundup and herbicides has actually developed super-weeds. This was a fun podcast on RadioLab, which you might enjoy - it's about an old English cure for MRSA and why it may have been abandoned, and yet, it now works again: http://www.radiolab.org/story/best-medicine/

    Maui Jungalow

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