A new class of antibiotics destroys resistant strains of bacteria
A new class of antibiotics has recently been developed to treat infections caused by antibiotic-resistant strains of bacteria. The mechanism of action of these antibiotics consists in destroying deadly superbugs, such as MRSA (methicillin-resistant staphylococcus areus), by destroying their cell walls. In addition, superbugs can now mutate into forms resistant to this class of antibiotics.
Kim Lewis, a professor of microbiology at Boston University, and his colleagues reported their discovery in the journal Nature.
Many of the antibiotics used today were first synthesized decades ago, and since then microbes have begun to develop resistance. to them.
Now a number of strains have appeared that are impossible to destroy with ordinary antibiotics, scientists call them antibiotic-resistant strains or “superbugs”.
For example, according to data from the World Health Organization /WHO/, in 2012 there were about 450,000 new cases of multidrug-resistant tuberculosis worldwide. These strains were found in patients from patients in 92 countries.
The bacteria that cause the most common infectious diseases, such as urinary tract infections, pneumonia, sepsis – are also becoming increasingly resistant to modern antibiotics and are difficult to treat.
For example, a large proportion of nosocomial infections are caused by a highly antibiotic-resistant special form of staphylococcus – methicillin-resistant Staphylococcus aureus / MRSA /.
The current situation brings us closer to the “post-antibiotic era”. This means that if we don’t find a way to deal with the current problem, the day won’t be far when antibiotics stop working and we’ll be back where we actually started – people will once again start dying from the most minor injuries and infections.
Most antibiotics used today in medicine and veterinary medicine were isolated from soil microbes – for millions of years they produced toxic compounds to protect themselves from other dangerous bacteria. For example, penicillin, the first successful antibiotic, originated from the soil fungus Penicillium.
But there is a serious problem with the study of soil bacteria – they are very difficult to cultivate in laboratory conditions. This means that about 99% of the microbes on planet Earth have not yet been sufficiently studied as a source of new antibiotics simply because the conditions for their growth and development in laboratory conditions cannot be created.
Professor Lewis and his developed method of cultivating bacteria in their natural habitat. This uses a device they call a “diffusion chamber”, thanks to which the soil bacteria are separated into separate chambers separated by 2 semi-permeable membranes. After filling the device, it is returned to the soil.
In this way, through the semi-transparent membrane, the bacteria are exposed to a complex assemblage of other microbes and compounds in the soil and grow under natural conditions.
In this way, the scientists obtained colonies of bacteria large enough to be able to study them already in laboratory conditions.
By reusing the diffusion chamber, the group of scientists examined about 10,000 bacterial colonies in an attempt to discover a new compound possessing the property to stop the growth and reproduction of Staphylococcus aureus.
They isolated 25 potential new antibiotics, one of them, called teixobactin, proved to be the most powerful.
In laboratory conditions, teixobactin caused the destruction of a wide range of pathogenic bacteria, including the superbugs MRSA and VRE /vancomycin- resistant enterococci/.
