UNITED STATES, WASHINGTON (OBSERVATORY) — Everything living from a person to a cockroach is constantly evolving, adapting to changing living conditions. No exception and the inhabitants of the microworld – bacteria.
Throughout the history of the struggle of humanity with pathogens, they change in response to the introduction of new antibiotics and “come up” with unusual survival strategies.
For example, one of the ways to “hide” from the action of drugs is to make certain changes in the genome that make microbes invulnerable (by the way, here geneticists and microbiologists have countermeasures).
Microorganisms also learned to destroy or remove the drug if it still penetrates the bacteria. Also, pathogenic organisms can “freeze”, ceasing to grow and divide. Such behavior reliably hides pathogenic microbes from the keen eyes of the immune system.
The study of all these tricks and evolutionary innovations is a very important component of the work of microbiologists around the world. If scientists do not “open” the protective arsenal of bacteria, then, according to experts, already by 2050, 10 million people may die from curable diseases.
Thus, in this field of science there are real battles for human life.
A new study by scientists from Newcastle University has focused on yet another poorly understood mechanism that makes bacteria resistant to even the most modern antibiotics.
To better understand the essence of this process, it is necessary to remember that almost all bacteria (as well as fungi and plants) have a cell wall.
This dense shell protects them from external influences, protects them from tearing and gives bacteria the desired shape (for example, sticks or spheres). In addition, the cell wall is involved in the efficient division of microorganisms.
“Since human cells do not have a cell wall, our immune system easily recognizes bacteria as foreign. It is the cell wall that serves as an excellent target for some of our best and most commonly used antibiotics, such as penicillin,” says one of the authors of a new scientific work, Katarzyna Mickiewicz.
Just in case, we explain that the cell wall and the cell membrane that separates the contents of a cell, for example, a person from the outside world, are different concepts.
As a result, antibiotics that “target” the cell wall kill the bacteria without harming the cells of the human body.
Nevertheless, microbes sometimes survive without their outer protective layer (the cell wall is located outside the cell membrane of bacteria). If the surrounding conditions are sufficiently favorable and protect them from rupture, microorganisms can live in the so-called L-form . In fact, these are bacteria completely or partially deprived of their outer cover.
In 1935, the development of such unusual forms drew the attention of Emmy Klineberger-Nobel. Special microorganisms received the first letter of their name in honor of the Listerovsky Institute, where the researcher worked at that time.
Although scientists have long suspected that the transformation of bacteria into L-form is one of the leading mechanisms responsible for antibiotic resistance, there was no evidence of this theory in the hands of scientists.
The fact is that the researchers did not have methods for detecting these “elusive” microscopic pests in samples taken from the human body.
However, this has become possible thanks to the so-called fluorescent probes , which “recognize” bacterial DNA.
Specialists at the University of Newcastle worked with urine samples from 30 patients with recurrent urinary tract infections. Samples were taken every two weeks for six months. So scientists were able to collect a whole database of 360 samples.
They placed the material in high sugar culture media. The latter creates the very safe environment for the “naked” bacteria and, accordingly, helps to isolate the living L-forms present in the urine.
As a result, British microbiologists for the first time convincingly showed that many types of bacteria, including E. coli and Enterococcus, actually survive antibiotic treatment.
And this happens due to the formation of L-forms, calmly continuing to live in the human body and causing repeated pyelonephritis and cystitis.
Moreover, scientists found that after discontinuing antibiotic treatment, these elusive “hiding” forms restored their cell wall again.
This study, among other things, shows how important it is to test antibiotics in conditions that are closest to the human body.
Unfortunately, when conducting a test for the sensitivity (or resistance) of bacteria to antibiotics, materials are often used that do not allow the survival of potentially dangerous but fragile L-forms.
Thus, such an analysis will not reveal the cause of a constantly recurring disease and will not “find” a suitable antibiotic.
According to the authors of the study, it is necessary to carry out new work in order to finally understand how important the mechanism of the transformation of bacteria into “invisible” forms is compared with other mechanisms of antibiotic resistance.
Who knows, it is possible that a mixture of drugs that simultaneously destroy the cell wall of pathogens and target L-forms can be the key to overcoming the resistance of bacteria to drugs, Mitskevich adds.
More information on the study of British microbiologists can be found in Nature Communications.
This article is written and prepared by our foreign editors writing for OBSERVATORY NEWS from different countries around the world – material edited and published by OBSERVATORY staff in our newsroom.
OBSERVATORY NEWS — Breaking news source, real-time coverage of the world’s events, life, politics, business, finance, economy, markets, war and conflict zones.
Contact us: firstname.lastname@example.org
Stay connected with News Observatory and Observatory Newsroom, also with our online services and never lost the breaking news stories happening around the world.
We are NEWS OBSERVATORY — the only funding and support we get from people – we are categorically not funded by any political party, any government somewhere or from any grouping that supports certain interests – the only support that makes OBSERVATORY possible came from you.