Creation of synthetic molecule shows promise in the fight against anti-microbial resistant bacteria
An international study involving Irish researchers has led to the creation of a new molecule that could help in the fight against antibiotic-resistant bacteria.
Scientists at Maynooth University (MU) took part in the research, which harnessed the principles of supramolecular chemistry, a niche scientific area that explores interactions between molecules.
The study uncovered molecules that are efficient at killing bacteria but whose toxicity to healthy human cells is very low. It is hoped that this discovery will prove significant in the fight against bacteria showing anti-microbial resistance (AMR).
“We are discovering new molecules and looking at how they bind to anions, which are negatively charged chemicals that are extremely important in the context of the biochemistry of life,” said lead researcher Luke Brennan of MU’s Department of Chemistry “We are laying the fundamental foundations that could prove useful in combatting various diseases from cancer to cystic fibrosis.”
The work is based on the use of synthetic ion transporters. It is the first time that researchers have demonstrated that an influx of salt (sodium and chloride ions) into the bacteria can cause a series 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).
Study co-author Dr Rob Elmes, of MU’s Kathleen Lonsdale Institute for Human Health Research, said: “This work shows how using our approach, a sort of ‘trojan horse’ that causes an influx of salt into cells, we can effectively kill resistant bacteria in a way that counteracts known methods of bacterial resistance”.
Bacteria work hard to maintain a stable concentration of ions inside their cell membranes, and when this delicate balance is disrupted, it wreaks havoc on normal cell function and the cells cannot survive.
Dr Elmes added: “These synthetic molecules bind to chloride ions and wrap it up in a ‘fatty blanket’ that allows it to easily dissolve in the bacteria’s membranes, bringing the ions along for the ride and disrupting the normal ionic balance. The work is a great example of foundation knowledge in chemistry fundamentals impacting on unmet needs in human health research.”
The research findings were published in the journal Chem to coincide with World AMR Awareness Week (November 18-24). Globally it is estimated that more than 1.2 million people died in 2019 as a direct result of antibiotic-resistant bacterial infections.
In Ireland, the second One Health National Action Plan on AMR (2021–2025) is seeing Government departments, agencies and stakeholders across human and animal health and the environment work together on policies to combat AMR.
The latest findings from the Health Ireland survey showed this week that more than four-in-ten people (41 per cent) reported taking an antibiotic in the last 12 months, significantly higher than the 27 per cent reported during the pandemic in 2021, and 2 per cent higher than the proportion in 2017.
“Antibiotics have revolutionised the way we treat patients with bacterial infections. To protect the effectiveness of antibiotics we have to use them appropriately,” said Chief Medical Officer Prof Breda Smyth.
“Raising awareness of the risks of antimicrobial resistance is very important to encourage behavioural change in how antimicrobials are prescribed and used.
“Ireland is taking a ‘One Health’ approach to addressing antimicrobial resistance. Our response is in keeping with the international approach recommended by the World Health Organisation and the European Commission. The One Health approach recognises that the health and wellbeing of people is connected to the health and welfare of animals, biodiversity, and the environment,” she added.