A new type of antibiotic kills bacteria without harming the microbiome

About the episode

Pathogenic Gram-negative bacteria, such as Escherichia coli, can defend themselves well against antibiotics and often acquire resistance. Different types of bacteria in this group can cause diseases such as salmonella and cholera.

There are effective treatments, but many of these medications also kill the good bacteria in our digestive system. Scientists may now have found a solution to this. They have developed an antibiotic that kills pathogenic Gram-negative bacteria without attacking the healthy microbiome.

This positive effect has only now been proven in mice, but if the same works in humans, the discovery could have a major impact. Although it remains to be seen whether resistance will develop in the long term.

To bypass the protective wall of these types of bacteria, researchers studied a substance that does not kill bacteria, but affects a specific network in the bacteria. A network of proteins is unique to this type of bacteria and is called the “Lol system.”

For example, they discovered that a substance called lolamicin kills pathogenic bacteria, but not healthy bacteria, because it responds to a difference in the composition of proteins in the Lol network.

This treatment has been successful against more than 130 types of resistant bacteria in the laboratory. The bacteria have also been successfully defeated in mice. And this without harming the healthy microbiome.

This all sounds like good news, but a cure for humans, if it appears, will take some time. In the past ten years, about ten to twenty new antibiotics have been developed against Gram-negative bacteria, none of which have been approved in the United States, where this study was conducted.

Read more about the research here: “Smart” antibiotics can kill deadly bacteria while preserving the microbiome