In April, the World Health Organization released the first global report on drug resistance, in which experts warned “the world is headed for a post-antibiotic era, in which common infections and minor injuries which have been treatable for decades can once again kill.” Now, scientists from the University of East Anglia in the UK say they have made a breakthrough in the fight against drug resistance.
Drug resistance, also referred to as antimicrobial resistance, is the ability of microbes – such as bacteria, viruses, fungi or parasites – to develop in the presence of drugs that would usually kill or stunt their growth. Such microbes are deemed “superbugs.”
The main function of microbes is to reproduce, rapidly spread and survive in the body. They do this by adapting to new environments. When an antibiotic stops the microbes from growing, they can undergo genetic changes that allow them to survive and create a defensive barrier, which is how antimicrobial resistance occurs.
In this latest study, recently published in the journal Nature, researchers have discovered how the defensive barriers of superbugs are built, which could lead to the development of new drugs to which bacteria are unable to develop resistance.
To reach their findings, the team analyzed a class of bacteria called gram-negative bacteria. Certain types of gram-negative bacteria – such as Escherichia coli – have become increasingly resistant to antibiotics.
According to the researchers, the cells of gram-negative bacteria have a dense lipid-based outer membrane that acts as its defensive barrier, protecting it against attacks from the human immune system and antibiotics.
It has been unclear as to exactly how the bacteria creates its defensive barrier, until now.
The research team, including Prof. Changjang Dong of the Norwich Medical School at the University of East Anglia, have discovered how the cells of the bacteria transport lipopolysaccharides to their outer surface, therefore building a protective barrier.
“We have identified the path and gate used by the bacteria to transport the barrier building blocks to the outer surface. Importantly, we have demonstrated that the bacteria would die if the gate is locked,” explains Prof. Dong, adding:
“This is really important because drug-resistant bacteria is a global health problem. Many current antibiotics are becoming useless, causing hundreds of thousands of deaths each year.
The number of superbugs are increasing at an unexpected rate. This research provides the platform for urgently needed new generation drugs.”
Lead study author Haohao Dong, also of the Norwich Medical School at the University of East Anglia, says that as a result of this research, new drugs may be able to attack the defensive barrier of bacteria rather than the bacteria itself.
Talking to Medical News Today, Prof. Changjang Dong explained:
“If we target the machinery for building the outer barrier of the bacteria, that means the drugs just need to attack the outer surface of the bacteria. [The drugs] will not necessary go inside the bacteria and will not be subject to bacterial efflux that pumps out the drugs, which are two main drug resistance methods bacteria have. Therefore, pathogenic bacteria will hardly develop resistance against the drugs we will develop using this approach.”
He told us that the team are now working on the development of small molecules that specifically target the defensive barrier of bacteria.
Medical News Today recently reported on a study, also published in the journal Nature, which suggests that studying drug resistance in soil bacteria may help defeat superbugs.