Nature antibiotic on leaves of wild field plants isolated

Researchers discover new antibiotic on leaf surface of a field weed

Swiss researchers have discovered a novel, antibiotic-effective chemical substance on the leaf surface of a widespread field weeds. Their results show that this microcosm conceals many unknown natural products that could make new drugs possible.

Danger from multi-resistant germs is getting bigger

The World Health Organization (WHO) recently warned of a looming increase in the number of multidrug-resistant bacteria. The increase in antibiotic resistance is an ever greater danger to humanity. If such drugs are no longer effective, even small inflammations can be a major risk. If the problem is not brought under control soon, there could be about ten million deaths from multidrug-resistant bacteria by 2050, according to an older study. A discovery by researchers from Switzerland could now offer opportunities to overcome existing antibiotic resistances.

Antibiotic resistance is becoming an ever greater threat to healthcare. A new discovery could now provide opportunities to overcome such resistance. And with the help of a discovered novel antibiotic on a field weed. (Image: jarun011 / fotolia.com)

Bacteria produce bacteria themselves

Many of the antibiotics used today have been developed on the basis of natural products that bacteria produce themselves to repel other bacteria. Wanted and found these substances especially in the soil.

Various scientists assume that active substances against resistant germs could also come from the earth in the future.

However, Julia Vorholt and Jörn Piel from the Institute of Microbiology at the Swiss Federal Institute of Technology (ETH) Zurich have now turned to a completely different ecosystem: the leaf surface of plants.

In a project supported by the Swiss National Science Foundation (SNSF) as part of the National Research Program "Antimicrobial Resistance" (NRP 72), they study bacterial strains from the leaf surface of thale cress (Arabidopsis thaliana).

This microcosm, called phyllosphere, is very nutrient-poor. "This leads to great competitive pressure," Vorholt is quoted in a statement by the SNSF.

"That's why bacteria produce a wide variety of substances that help them defend their habitat."

For despite the scarce food supply populated by a variety of organisms, the phyllosphere. Vorholt and Piel examined more than two hundred bacterial strains, all of which are found on the common wild European plant Acker-Schmalwand.

Overcome existing resistance

Although their genomes were decrypted for the strains, they have so far hardly been specifically analyzed.

The scientists found a total of 725 antibiotic interactions between different strains, which means that certain bacteria no longer multiply.

"The big question was, of course, whether we only found substances that are already known from other habitats or whether we came across compounds with completely new properties," says Piel.

This would be extremely important for antibiotic research: It is looking for new antibiotics with mechanisms of action, which differ significantly from those of the current drugs and thus overcome existing antibiotic resistance.

Absolutely novel chemical structure

To determine whether new antibiotics are available, the Swiss researchers had to study the exact chemical compositions in detail.

They did so for gene clusters and substances from a single bacterial strain that has proven to be a particularly active producer.

They discovered several antibiotic chemicals. One of them, named by the researchers Macrobrevin, has an absolutely novel chemical structure.

The results of the study were published in the journal "Nature Microbiology".

Expanding the search for antibiotics in nature

"We will now clarify whether Macrobrevin and other newly discovered substances also act against bacteria that cause disease in humans," says Piel.

But even higher than this possibility, he estimates the success of having shown that there are still many natural substances to be discovered for antibiotics in the previously under-researched phyllosphere:

"This incredibly diverse ecosystem can certainly provide many new approaches to medicine. Our results confirm that it is worth expanding the search for antibiotics in nature. "(Ad)