Replacing habitual antibiotics with synthetic molecules from IBM


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IBM researchers are working on substances that can fight bacterial resistance to antibiotics. The picture shows one of these bacteria, MRSA (Methicillin-resistant Staphylococcus aureus, methicillin -resistant Staphylococcus aureus). It is assumed that synthetic drugs can help in confronting the continuous evolution of bacteria.

The discovery of penicillin by Alexander Fleming in 1928 is important for two reasons: first, doctors received the long-awaited opportunity to fight diseases like pneumonia, gonorrhea and rheumatic fever. Before this, there was no method except how to expect, observing and relying on the fate and the work of immunity; Understandably, that often for the patient this ended tragically. Secondly, the discovery led scientists to another idea - “what if those substances that emit bacteria or fungi, can be used in the attack and other infectious diseases?”.

And from that time began a continuous search for new molecules, like penicillin, in order to combat the hordes of bacteria and fungi that infect us. This is a fierce race in which time plays against people. Bacteria change at high speed, and while we are trying to destroy them, they are trying to survive - by any means. The most unpleasant thing here is that in such a competition of "rope pulling", microorganisms are clearly being pulled to their side with a fair margin . In May 2016, a group of researchers, called “Control of microbial resistance to drugs”, found that approximately 700,000 people a year die from antibiotic-resistant diseases (caused by bacteria, against which none of the existing antibiotics no longer work). By 2050, an annual mortality rate of up to 10,000,000 people is projected, unless other treatments are found.

Science does its best to prevent this. In the meantime, the bulk is occupied by what Fleming did — sifting bacteria and fungi for suitable substances, IBM researchers chose an alternative route, creating a synthetic molecule that destroys bacteria from the inside.

The development proceeds from the most terrible scenario of infection: resistance of the pathogen to antibiotics, systemic infection, multiple organ failure . And they managed to construct a substance that effectively works against the five most famous species, distinguished by their resistance to drugs, those that often infect directly in hospitals and quickly seize the body, causing a complete failure of all organs.

Of course, the work on synthetic pharmaceuticals did not begin yesterday, but the tasks still do not become simpler. It is necessary to make the agent biodegradable - because it does not have to linger in a person for a long time - and not allow healthy tissue to be killed along with the infection. For example, “last chance” antibiotics are extremely toxic, and together with bacteria they affect the liver, as well as other systems.

“We are trying to imitate immunity,” says James Hendrick from IBM. He and his team published the accumulated material in the journal Nature Communications. "The immune system cures the germ and decomposes its cell membrane," the scientist writes, "We destroy invading alien cells by suppressing their own defense mechanisms." "When you get sick, the body produces antibacterial peptides - in other words, polymer chains" (that is, in fact, long protein molecules). Recently, many laboratories have focused on the synthesis of such molecules.

According to Hendrick, the main difficulty is that toxins from the "killed" infected cells get into the blood. For single or small quantities, this is tolerable. But with systemic infections, the bill goes to millions, and the toxic effect can be terrible.

Previously, Hendrick adds, synthetics used a similar approach, “bursting” every bacterium. Now they work from the inside.

In addition to what has been said, the Hendrick associates believe that this type of medicine can even reduce the resistance of bacteria to antibiotics in general. The polymer uses electrostatic interaction - the attraction of positive and negative charges. But there are many such points of attraction on the surface of the bacterium, and this means that even with some mutations of the strain, there will still be a place for which you can catch on.

According to IBM reports, the polymer is fully biodegradable and works extremely quickly. “It's great that the new class of materials after three days completely breaks down. In fact, it is introduced, does its job, decomposes, and leaves the body. "

At the moment, the drug has only been tested on mice, but Hendrick thinks it’s time to subject the formula to clinical trials in humans. For IBM, this means working with pharmaceutical companies to organize the necessary tests, and later - developing a specific drug based on the results.

It sounds good, but from the laboratory table to the shelf in the pharmacy, the path is not close. Positive tests on mice do not mean that everything will automatically work the same way on a person. The greatest concern is the likelihood of accumulation of substances in our body. The predecessors of this polymer were rejected precisely because they did not properly split and were not removed.

There is skepticism about the cost. Synthesis is more expensive than antibiotic production technologies used in the pharmaceutical industry, and this will raise the price for both manufacturing companies and end-users.

Even if the high efficacy of this remedy is proved, the world will still not abandon the search for other methods to cure diseases without the use of antibiotics - as well as ways to slow the growth of resistance. In the latter, a decrease in the number of Cesarean can help; prohibition of taking antibiotics for infections that do not respond to them (such as flu or a cold) or those with which the immune system is able to cope on its own; reduction in the use of antibiotics in the food industry .

Although the drug will for some time inhibit the progress of bacteria in the field of drug resistance (Hendrik does not undertake to predict how long), it will not last forever. “Bacteria are very“ smart. ” It will take several decades, and they will figure out how to avoid our polymer, ”warns Hendrik,“ Therefore, the war with them will never end. ”

With more detailed article about this substance (guanidine-functionalized polycarbonates) anyone can read here (in English).

Source: https://habr.com/ru/post/411155/


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