American chemists have created an antibiotic that kill «superbugs»

© Fotolia / analysis121980Выращивание bacteria on a nutrient medium in the laboratoryAmerican chemists have created an antibiotic that kill «superbugs»© Fotolia / analysis121980

. American biochemists have modified the structure of the antibiotic vancomycin so that it began to destroy the germs that have developed resistance to the original version of this medication, according to a paper published in the journal PNAS.

«Doctors can use this version of vancomycin without fear that microbes will develop resistance to its molecules. It acts on the bacteria in three different ways, so that his vitality has increased dramatically. Germs simply cannot look for ways to solve three different tasks – even if they manage with a mechanism of action, the other two will kill,» said Dale Boger (Dale Boger) from the SCRIPPS Institute in La JOLLA (USA).

In recent years, professionals are more and more it becomes a problem of occurrence of so-called «super-bugs» – germs resistant to one or more antibiotics. Among them are rare pathogens and very common and dangerous pathogens, such as Staphylococcus aureus (Staphilococcus aureus) or Streptococcus pneumoniae (Klebsiella pneumoniae). There is a real danger that all antibiotics will lose their effectiveness and medicine back to the dark ages.

The main «incubators» of such microbes, as scientists believe today, are the hospitals and livestock farms, where antibiotics are used to accelerate the growth of beef cattle. And on farms, and in hospitals there are large number of potential infections, and the bacteria, and antibiotics, causing them to evolve and not giving a «normal» bacteria to crowd out less prolific super-germs.

As stated, Boger and his colleagues, they managed to find a potential solution to this problem by modifying one of the «antibiotics of last resort», vancomycin, to which some microbes have already started to develop resistance due to the fact that it is used in medical practice for nearly 60 years.

A team of Bougara for several years developing new versions of this antibiotic, the creation of which scientists are not just trying to increase its efficiency, but to make the molecule «immune» to the evolutionary processes that cause germs to evolve into «superbugs».

To solve this problem, the researchers analyzed the three-dimensional structure of the molecules of vancomycin and followed the way he interacts with the cell wall of microbes and highlighted all the «weak spots» in the molecule which counteract the bacteria in the first place.

Guided by these observations, biologists have identified three of the most active and vulnerable points in the molecule and changed their structure so that each of them could independently connect with the cell wall of bacteria and to interfere with its normal «build» and work. Some of these changes are already present in the derivatives and analogues of vancomycin that has facilitated the task of their «transplant» in the original antibiotic.

The product of all these changes was a new molecule, whose antimicrobial activity was 25 thousand times higher than vancomycin. However, she suppressed reproduction and even kill those germs that have developed complete resistance to its «progenitor», including enterococci that cause infections of the gastrointestinal tract in hospitals. Moreover, antibiotic has not lost its power even after 50 attempts to breed the germs in his presence.

Scientists expect this version of vancomycin must live not less, than its progenitor, about 50 years before microbes will start to develop resistance to it. Moreover, Boger and his colleagues believe that the bacteria cannot adapt to such «triple» the attack in principle, if the derivatives of vancomycin, one of three such changes will not be used in the future.

The main issue of this improved «version» of the antibiotic is the complexity of its production – it includes 30 different stages and is fairly complex reactions. According to Bogere, this is not a problem, and their number can be reduced today to 26 or even 18 feet, and in the future – and to an even smaller numbers.