An international team including researchers from Maynooth University has developed a new molecule that has the potential to combat drug-resistant bacteria. Antimicrobial resistance (AMR) is a phenomenon in which bacteria, viruses, fungi and parasites evolve over time to become immune to drugs. This resistance makes the infection more difficult to treat, increasing the risk of prolonged illness and death.
It is predicted that by 2050, traditional antibiotics will have largely lost their effectiveness due to rising AMR levels, so finding new ways to eradicate the bacteria has become a top priority for the scientific community.
Supramolecular chemistry: the key to fighting AMR
This research leverages the principles of supramolecular chemistry, a niche scientific field that explores interactions between molecules, to achieve this breakthrough. Most importantly, the study identified molecules that are effective at killing bacteria but have minimal toxicity to healthy human cells.
The new research, published in the prestigious journal Chemistry, coincides with World AMRAwareness Week, which runs from November 18 to 24. This global campaign launched by the World Health Organization aims to increase people's awareness and understanding of AMR, hoping to reduce the emergence and spread of drug-resistant infections.
More than 1.2 million people, and possibly millions more, died as a direct result of antibiotic-resistant bacterial infections in 2019, according to the most comprehensive estimate yet of the global impact of AMR. The research could pave the way for new ways to tackle a problem that kills more people every year than AIDS or malaria.
Lead researcher Luke Brennan, from the Department of Chemistry at Maynooth University, said: "We are discovering new molecules and studying how they bind to anions, which are negatively charged chemicals that are extremely important in the biochemistry of life. We are laying the foundation for the prevention and treatment of diseases ranging from cancer to cystic fibrosis."
Using a "Trojan horse" approach to combat drug-resistant bacteria
The work, based on the use of synthetic ion transporters, shows for the first time that the influx of salts (sodium and chloride ions) into bacteria can cause a cascade of biochemical events that lead to bacterial cell death - even in strains that are resistant to currently available antibiotics, such as methicillin-resistant Staphylococcus aureus (MRSA).
Dr Robert Elms, co-author of the study from the Catherine Lonsdale Institute of Human Health at Maynooth University, said: "This work shows that using our approach - a 'Trojan horse' that causes an influx of salt into cells - we can effectively kill drug-resistant bacteria in a way that counters known methods of bacterial resistance."
"Bacteria work hard to maintain a stable concentration of ions within their cell membranes," continued Elmes. "Once this delicate balance is disrupted, the cell's normal functions are disrupted and the cell cannot survive. These synthetic molecules bind to chloride ions and wrap them in a 'fat blanket,' allowing them to easily dissolve in the bacterial cell membrane, bringing ions within them and disrupting the normal ion balance. This work is an example of how basic knowledge of chemistry can impact an unmet need in human health research."
Professor Kevin Kavanagh, a microbiologist at the Department of Biology at Maynooth University, commented: "The rise in infection rates with drug-resistant bacteria is a major concern. This work is an example of chemists and biologists working together to develop new antibacterial agents with significant future potential."
These results pave the way for the potential development of anion transporters as viable alternatives to existing antibiotics, which is urgently needed as the problem of AMR continues to rise.