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New antibiotics against resistant germs come from the earth


Does simple soil contain the key to new antibiotics?

Is it possible that in the future drug-resistant bacteria can be treated with a new form of antibiotic that comes from the soil? Researchers have now found that microorganisms found in the earth appear to be the key to the production of new antibiotics.

A major breakthrough was achieved in an investigation into new effective antibiotics. Scientists at Rockefeller University in New York reported the discovery of a new class of antibiotics derived from unknown microorganisms living in the soil. The doctors published the results of their study in the English-language journal "Nature Microbiology".

Mold led to the development of penicillin

When a British scientist named Alexander Fleming discovered a bacteria-killing mold in one of his petri dishes, it was a revolutionary moment in the history of medicine. The researcher discovered penicillin, the world's first antibiotic.

Super pathogens are resistant to most drugs

But ninety years later, antibiotic-resistant pathogens were a major problem for society. Such so-called super-pathogens have already developed resistance to dozens of medications. This leads to infections, which are increasingly difficult to treat. Global deaths from antibiotic-resistant infections are expected to reach ten million a year by 2050, experts suspect. More and more medical professionals around the world are therefore trying to produce new, effective antibiotics.

New antibiotics come from the earth

In a recent study, the researchers did not try to grow antibiotics in a petri dish this time, instead they searched for them in the ground. The scientists at Rockefeller University in New York were looking for a reservoir of antibiotics, which naturally occurs in the environment. There are many bacteria in the earth whose behavior has not yet been researched, explains study author microbiologist Sean Brady.

Malacidines act against MRSA

The new class of antibiotics is called malacidine. It is able to kill various multi-resistant super-pathogens, including the dreaded hospital germ Methicillin-resistant Staphylococcus aureus (MRSA), without causing resistance. Unfortunately, it will still be years before a new molecule is developed, tested and approved for sale. In other words, Malacidine will not be available in the pharmacy any time soon. But the discovery is proof of a strong principle. A world of potentially useful untapped biodiversity is still waiting to be discovered, the expert adds.

Bacteria from the soil formed malacidines

In their study, the scientists took more than a thousand samples of soil from across the United States. They were looking for products from mold and soil microbes. The samples were examined to determine and analyze the bacteria contained therein. Such bacteria are able to form antibiotic agents themselves. Indeed, by decoding the DNA from the bacteria, the experts actually found genes that could form malacidines.

How do malacidines work?

Experiments have shown that malacidines are very effective against a number of bacterial pathogens. It was also possible to investigate how malacidines kill these pathogens from diseases. Malacidines attack a specific molecule, which means that the structure of the cell wall is disturbed and cell survival is no longer possible, the researchers explain.

Further tests on rats confirmed the effectiveness

Because of the high potential of malacidines as new antibiotics, the effectiveness was tested in further experiments on animals. The doctors used laboratory rats for this. The rats were infected with the multi-resistant Staphylococcus aureus hospital germ. This usually leads to a serious infection on the skin of the test animals. When applied to cuts in the skin of MRSA-infected rats, the previously unknown molecule successfully sterilized the wounds, the experts report. The bacterium showed no signs of resistance even after three weeks of exposure. The results showed that malacidines completely regenerated the skin. The animals finally became completely healthy again.

Malacidines do not cause resistance to develop quickly

The scientists now hope that malacidines will become effective antibiotics in the future, which could be used to treat previously resistant pathogens. In addition, another advantage seems to be that the use of malacidine does not lead to the fear of rapid development of resistance, the doctors presume.

Bacteria have developed effective weapons

Bacteria have been fighting with each other for billions of years, the experts say. It is therefore not surprising that bacteria have developed the most effective weapons. However, the vast majority of these microbes do not grow well under controlled laboratory conditions, making them difficult to study. It would be better to derive interesting molecules directly from the environment, the doctors explain. And with the advent of metagenomics, which allows mass sequencing of all genetic material in a sample, researchers can do just that. (as)

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Video: The Threat of Antibiotic Resistance (August 2020).