Stick insect leads antibiotic hunt, Norwich researchers say Published duration 31 August 2013

image caption The gut of the giant lime green stick insect could hold the key to antibiotic resistance

A microbe in the gut of a stick insect could help scientists to unravel the puzzle of antibiotic resistance.

The giant lime green stick insect, which feeds mainly on eucalyptus leaves, is being studied at the John Innes Centre (JIC) in Norwich.

In the laboratory it has shown resistance to toxins and infections it could never have encountered before.

This indicates a general mechanism at work and understanding this could lead to new drugs, JIC scientists believe.

Scientists at JIC are confident studying natural processes will reveal new antibiotics.

The pressure is on to make discoveries because every year more drugs are made ineffective by microbe resistance.

Ants carry antibiotic

Professor Tony Maxwell, head of biological chemistry, said: "We have discovered the microbe in the stick insect's gut is resistant to toxins and infections it could never have been exposed to.

"This indicates that there is a general mechanism at work.

"If we can unravel that then it opens the way to understanding antibiotic resistance and this will enable us to build a chemical strategy against it.

"It will also help us build into new antibiotics a mechanism to counter any resistance."

BBC Inside Out discovered researchers were also looking for new antibiotics in the soil.

Professor Mervyn Bibb's laboratory at JIC has produced an antibiotic candidate which may now undergo clinical trials.

About half of the antibiotics used today originated in soil bacteria which is why scientists continue to study them.

One early breakthrough in the search for new antibiotic strains came with the discovery that leafcutter ants in tropical forests carried a substance on their bodies that protected the integrity of a fungus food source.

The ants mulched leaves to allow a fungus to develop.

Government initiative

To protect this food source from unwanted microbes and parasites and to regulate the growth of the fungus the ants carry a highly effective wide spectrum antibiotic on their bodies.

media caption Scientists are harvesting the antibiotic made by leafcutter ants

The antibiotic's properties are similar to antifungal agents used in modern medicine.

Project leader Dr Matt Hutchings from the University of East Anglia hopes studying leafcutter ants will uncover completely new antibiotics.

Government health officials have issued a fresh warning about the urgent need to find new antibiotics.

The UK's deputy chief medical officer, Professor David Walker, said: "If we don't take action now, antibiotic resistance could mean that widely used treatments for diseases including cancer and common operations such as hip replacements could become impossible.

"If we don't take action now we could face a situation when some common infections become untreatable."

The government has recognised it may have to step in to fund development and a new initiative is being formulated.