Potential breakthrough in antibiotics — up your nose
Scientists hunting for new antibiotics have scooped them from soil. They have searched in oceans and caves. And now, they are picking them out of your nose.
In a paper published Wednesday in the journal Nature, German researchers report the discovery of a new antibiotic produced by a bacterium that lives inside the human nostril.
Experts say the paper is fascinating not just for the discovery of a potential new antibiotic — one that can kill a superbug called MRSA — but because it opens a potential new frontier in the desperate search for novel antibiotics: ourselves.
“Finding a new antibiotic is relatively rare. In the human microbiome, it’s super rare,” said Gerry Wright, an antibiotic resistance expert with McMaster University who was not involved with the study. The human “microbiome” refers to the trillions of microbes that live on our skin and in our guts.
“It’s yet another great example of looking where people have rarely looked before — and finding something cool.”
This paper is just the latest effort to stave off what public health officials are calling a “post-antibiotic era” — a time when bacteria are resistant to all available antibiotics and a scraped knee or run-of-the-mill infection can kill.
People are already dying from once-treatable infections and deaths caused by superbugs, “are expected to become more frequent causes of death than cancer in the coming decades,” according to the study.
This crisis has renewed efforts to find new antibiotics and scientists have become increasingly creative in their search, with a handful of promising new compounds recently unearthed.
A starting point for this latest study was the observation that the bacterium Staphylococcus aureus, a common cause of infection, can be found in the nostrils of roughly 30 per cent of people.
These people are not necessarily infected — just “colonized” — though this bug is an opportunistic pathogen, causing pneumonia or serious infections in people who are sick or immuno-compromised.
The researchers asked themselves: what’s going on in the noses of people who aren’t harbouring this pathogen? One difference, they found, is the presence of another bacterium called Staphylococcus lugdunensis, which produces an antibiotic they’ve named “lugdunin.”
Analyzing the nasal swabs of 187 hospital patients, the researchers found that 9 per cent had this protective bacterium in their noses — and out of this group, only 6 per cent were colonized with Staphylococcus aureus.
In patients who didn’t have the bug, however, 35 per cent were colonized with Staphylococcus aureus.
“We started the project just for basic understanding (but) it led us to some very unexpected and exciting findings,” said co-author Andreas Peschel, a bacteriologist with the University of Tübingen.
“It was totally unexpected to find a humanassociated bacterium to produce an antibiotic. This is usually known from soil or environmental bacteria.”
Laboratory tests showed that lugdunin was effective at wiping out not just Staphylococcus aureus but also a superbug strain called MRSA, which is estimated to be 64 per cent more likely to cause death than nonresistant staph infections.
The antibiotic also cured mice infected in lab experiments.
The researchers don’t understand how, exactly, lugdunin is killing the bacteria and they say more work is needed to determine whether the antibiotic is safe or effective in humans.
They suggest that antibiotic-producing bacteria like Staphylococcus lugdunensis could someday be used as a probiotic, however, given to vulnerable patients to prevent staph infections.
They have also filed patent applications and hope to attract interest from drug companies. There are early signs that lugdunin might only be useful as a topical antibiotic — but even if everything goes well, it will take hundreds of millions of dollars and several years before the antibiotic is ready for market.