Antiseptic resistance in bacteria ‘could lead to next generation of plastics’
The armour that superbugs deploy to resist antiseptics could be used to create a new generation of plastics, a study suggests.
Scientists say the molecular machinery bacteria use to resist chemicals designed to kill them could produce precursors for nylon and other polymers.
Acinetobacter baumannii fights off a powerful hospital-grade antiseptic called chlorhexidine listed by the World Health Organisation as an “essential medicine”.
The bacteria can cause serious infections in hospital patients who are already unwell.
A study published in Proceedings of the National Academy of Sciences found that a protein called Acel sits on the surface of the bacteria and pumps out any chlorhexidine that gets inside.
Researchers say this is surprising because the protein has been around for a lot longer than the antiseptic.
Professor Ian Paulsen, of Australia’s Macquarie University, said: “Resistance to artificial antiseptics appears to be a lucky accident for the bacteria, and it could also be useful for humans.”
Dr Karl Hassan, from Australia’s University of Newcastle, added: “The gene that encodes the AceI protein appears to be very old but chlorhexidine was only created in the twentieth century.
“So, the gene can’t have the native function of protecting against chlorhexidine. It’s a side reaction that is fortunate for the bacteria.”
The researchers looked at what other compounds are transported by AceI and its relations, collectively known as proteobacterial antimicrobial compound efflux (PACE) proteins.
They found that PACE proteins are likely to be future engines of antimicrobial resistance.
Their ability to transport a wide range of substances means they could be effectively repurposed in an industrial context to catalyse the manufacture of petroleum-free polymers such as nylon, the study suggests.
Professor Peter Henderson, at the University of Leeds, said: “These PACE proteins are very promiscuous in the compounds that they transport and are a likely cause of future resistance to new antimicrobials that are currently being developed.”