How Does Bacteria Eat Antibiotics?
Bacteria have always interacted with antibodies, whether it be by disarming them by tying them up, pumping them out before they can work themselves or even eating them
But now, researchers can explain how these germs can actually do so, with such findings having the potential to help fight antibiotic-resistant superbugs in the future, writes NBC News.
“Ten years ago we stumbled onto the fact that bacteria can eat antibiotics, and everyone was shocked by it,” said Gautam Dantas of Washington University School of Medicine in St. Louis, who led the study team. “We think of bacteria eating things like sugar, but not antibiotics.”
Being able to understand how bacteria can do this can help in the design of new and better antibiotics, Dantas explained and can help some of the problems that help lead to antibiotic resistance in the first place, such as spills from factories that make the drugs; waste from farms where animals are fed antibiotics to make them grow; and hospital sewage.
This news comes when drug-resistant superbugs are found virtually everywhere. The Centers for Disease Control and Prevention claims in the U.S. alone, that more than two million people are infected by antibiotic-resistant germs each year, and 23,000 die of their infections. Globally, these microbes kill 700,000 people a year.
Dantas and his team figured out how, step-by-sep, some strains of bacteria can break down and eat antibiotics. They then went on to make their own version of drug-munching bacteria.
“One of the first things that these bacteria do to be able to eat the antibiotic is to make it less toxic, to detoxify it,” Dantas said. “Before you can eat the poison you need to inactivate it.”
The bacteria they discovered that eats antibiotics uses some of the same mechanisms as drug-resistant superbugs do. The results of which have been reported in the journal Nature Chemical Biology.
“The next thing we found is there are specialised enzymes that these antibiotic-eating bacteria have that chop these compounds down into bite-sized pieces,” Dantas noted.
Getting to grips with these steps can help scientists produce bacteria with the same qualities, and Dantas’s team did that, making E. coli that could live in a soup of antibiotics and actually break them down to get the carbon molecules that all life on Earth needs to survive.
“We applied this knowledge to design two strain of E. coli that can consume penicillin as a sole carbon source,” Dantas added.
The goal wasn’t to make scary superbugs in the lab, but instead to take a step toward designing something that could help clean up antibiotic pollution from factories, sewage or farm waste. In addition, understanding the mechanisms can help drug designers stay a step ahead of bacteria that constantly mutate and evolve new ways to resist the effects of antibiotics.
“People can take these building blocks and stitch them together in different ways,” noted Dantas, who helped found a company, Viosera, that develops new antibiotics.
He explained that it took his team ten years to first learn to work with the bacteria, to grow them, to sequence their genes and then experiment on them. “Not that we have figured out how to do it, we think that other people can do it,” he added.
That’s what science should be about, he continued. “You provide a recipe and someone else tweaks the recipe and makes it better.”
The positive is that the bacteria that commonly infect people haven’t acquired this drug-eating superpower – yet. “These antibiotic-eating bacteria are not disease-causing and, as far as we know, bacteria in the labs don’t eat antibiotics,” said Dantas.
However, it’s not likely that antibiotic-eating bacteria will evolve any time soon. None of the bacteria the team found prefer to eat antibiotics, instead, they just consumed it as if they had nothing else. “If you are in the human body causing an infection as a bad bug, you have lots of food sources,” Dantas concluded.