Crocodile immune system might help humans fight fungus

The reason why crocodiles stay healthy after being wounded in fights in filthy water could one day be used to treat infections in humans.

La Trobe University scientists have discovered how a protein in the predator's immune system can be switched on to fight fungal infections depending on its environment.

Significantly, these proteins - called defensins - are remarkably similar to those found in humans.

Lead author Scott Williams hopes the research, published in Nature Communications, can be used to develop the next generation of targeted fungal treatments.

"These proteins have been conserved throughout evolution, so if we've still got them today and crocodiles have them there's something really important about them we should be looking into," Mr Williams told AAP.

"If they're that important, potentially, we can develop them further and try and treat disease."

It's also the first study to document the structure of defensins in such a high quality, according to senior author Professor Mark Hulett.

Current fungal treatments not only attack infections but can also impact healthy cells and cause lasting damage.

Crocodile defensins, however, attach themselves to harmful fungi and open them, rather than impacting other cells.

This defence mechanism has sparked hopes it could be engineered to do the same in humans.

While the world 'fungal' may conjure images of itchy foot rashes, such infections are a serious health risk for immunocompromised patients in hospitals, particularly as antibiotic resistance grows.

Mr Williams said he was drawn to study crocodiles because of their unique survival skills.

"They're constantly fighting for territory, they lose limbs and are completely fine without developing infection ... there's something particularly interesting about crocodiles that makes them really resistant to developing infections and diseases," he said.

So far the predators are the only known animal or plant that has this mechanism.