Fungal foray-ing and the search for new antibiotics

Could the answer to one of our most pressing health needs be hiding in Aotearoa's bush? On Our Changing World this week, Liz Garton heads out on a foray to discover some of our fungal gems, and she finds out what we're doing to uncover their potential antibiotic properties.

Could the answer to the global problem of antibiotic resistant bacteria be in our backyard?

It's a question being given serious time and consideration by Dr Siouxsie Wiles and Dr Bevan Weir, with help from fungi enthusiasts around Aotearoa.

The problem

The World Health Organization describes antimicrobial resistance as one of the top global public health threats, responsible for an estimated 1.27 million deaths in 2019.

"Life is always fighting, so bacteria will find a way to fight against antibiotics," says Dr Bevan Weir, head of Mycology and Bacteriology Systematics Research at Manaaki Whenua / Landcare Research. "They'll evolve chemistry to cut the molecule and render it inactive or other forms of resistance - they can change their cell walls and pump out the antibiotic more."

"They're always finding a way to evolve around antibiotics, so we do need to find more," he says.

The foray

On a cool but sunny autumn morning in May 2023, Liz Garton joined The Fungal Network of New Zealand's annual foray at Maungatautari Sanctuary Mountain. The 2024 fungal foray is taking place now, from 12-18 May in Havelock.

Each year the foray is held in autumn when the fungi fruits, and it can be spotted.

Each fungus begins as a miniscule spore. From that grows the mycelium, a network of fungal strands, like string, and from those you get the fruiting body. The fruiting body is the bit we see sprouting out of the ground, or whatever the organism is growing on - what we call a mushroom.

Bevan says one of the main reasons for the foray is to take samples for the national culture collection (which he curates) and to try identify and describe what is found.

"That's one of the big questions we don't know; what fungi is native and what are not," he says. "We have probably only described or identified about a third of the fungal biodiversity in New Zealand."

With that unidentified diversity comes diversity of chemistry too. A fungus growing on a piece of wood needs to defend itself and compete with bacteria.

"So it will be producing an antibacterial to kill that bacteria and we might be able to discover what that is and use it for us in a medical context," says Bevan.

The (possible) solution

This brings us to the work Bevan is doing with microbiologist Dr Siouxsie Wiles at the University of Auckland…

Go to this episode on rnz.co.nz for more details