New gene editing tool may help reduce spread of antimicrobial resistance

Scientists have developed a new gene editing tool which could help reduce the spread of antimicrobial resistance.

Antimicrobial resistance is a major global threat, with nearly five million deaths annually resulting from antibiotics failing to treat infection, according to the World Health Organisation.

Bacteria often develop resistance when resistant genes are transported between hosts. One way this occurs is via plasmids circular strands of DNA, which can spread easily between bacteria, and swiftly replicate. This can occur in our bodies, and in environmental settings, such as waterways.

The researchers at the University of Exeter in the UK harnessed the CRISPR-Cas gene editing system, which can target specific sequences of DNA, and cuts through them when they are encountered.

The team engineered a plasmid which can specifically target the resistance gene for Gentamicin a commonly used antibiotic.

In laboratory experiments, the research, published in the journal Microbiology, found that the plasmid protected its host cell from developing resistance.

The researchers also found that the plasmid effectively targeted antimicrobial resistant genes in hosts to which it transferred, reversing their resistance.

Antimicrobial resistance threatens to outstrip Covid in terms of the number of global deaths. We urgently need new ways to stop resistance spreading between hosts,” said study lead author David Walker-Snderhauf, of the University of Exeter.

“Our technology is showing early promise to eliminate resistance in a wide range of different bacteria. Our next step is to conduct experiments in more complex microbial communities,” Walker-Snderhauf said.

The researchers hope that one day the technology could provide a way to reduce the spread of antimicrobial resistance in environments such as sewage treatment plants, which are breeding grounds for resistance.