Good Gut Bacteria

Researchers of synthetic biology based at the Massachusetts Institute of Technology (MIT) in the US have devised a system to protect the gut microbiome from the effects of antibiotics.

The new study, published in Nature Biomedical Engineering, reports on the successful use in mice of a “live biotherapeutic” – a genetically engineered bacterium that produces an enzyme which breaks down antibiotics in the gut.

“This work shows that synthetic biology can be harnessed to create a new class of engineered therapeutics for reducing the adverse effects of antibiotics,” says MIT professor James Collins, the paper’s senior author.
The dark side of antibiotics

Antibiotics – substances that kill or inhibit the growth of bacteria – are hugely important in fighting bacterial infections.

But there’s a dark side to antibiotics too. Increasing human use of antibiotics has contributed to the rise of antibiotic resistance, which has made many bacterial diseases increasingly difficult to successfully treat.

Antibiotic treatment can also kill off bacteria in our resident healthy gut microbiome – the trillions of microbes that live in our gastrointestinal tract and assist with food digestion, immune development and vitamin synthesis.

This causes two problems: firstly, we can lose the benefits provided by our good bacteria; and secondly, this disruption can tip the balance of the microbial ecosystem towards species that cause harm.

In some cases, these indiscriminate effects of antibiotics can have life-threatening consequences. In the US, about 15,000 deaths each year are attributed to diarrhoea and colitis (inflammation of the colon) caused by overgrowth of the bacterium Clostridium difficile following antibiotic overuse.

So, while antibiotics are an important and necessary tool to fight bacterial infections, working to limit antibiotic resistance and damage to the gut microbiome are key priorities for research.  READ MORE...