Scientists working in the jungles of Borneo report an unsettling discovery: a parasitic organism that they say has a hunger for zombie fungi.

This “hyperparasite” fungus thrives, according to Malaysian scientists behind the discovery, by feeding on forms of fungi that are known to infect insects and temporarily take control of them before ultimately killing them.

The unusual fungus was discovered during field trips by researchers with the University of Malaysia Sabah’s Institute for Tropical Biology and Conservation, who have designated it a hyperparasite because of its unique strategy of feeding through parasitizing another parasite organism.

A Hyperparasitic Zombie-Killer

“The fungus belongs to the genus Pleurocordyceps and acts as a specialized hyperparasite,” said Jaya Seelan Sathiya Seelan, the institute’s deputy director, in a statement provided to AFP last week.

In the television show and related video game series, The Last of Us, a unique approach to the idea of a zombie apocalypse is presented, where humans can become infected by a novel variety of cordyceps. Fortunately, in real life, these parasitic fungi only manipulate insects by hijacking their nervous systems and temporarily taking control of their bodies for a time.

The infected insects begin engaging in erratic behavior as the parasitic fungus takes hold, which eventually fills their bodies and then bursts out in a final, gruesome death for the unlucky host.

A Horned Hyperparasite

The newly discovered “hyperparasite,” Pleurocordyceps cornusynnemata, garners its name from a distinctive horn-shaped appearance, and works by targeting insects—namely tropical ants—which have already been infected by a variety of zombie fungus known as Ophiocordyceps.

“Rather than manipulating the insect’s nervous system itself, Pleurocordyceps infiltrates and feeds directly on the thriving Ophiocordyceps tissue inside the host,” Seelan recently explained, adding that the unique fungus was discovered while investigating a dead ant specimen that was collected from the Danum Valley in southern Sabah.

Although Pleurocordyceps cornusynnemata is not the first hyperparasite fungus known to science, Seelan said it is the first recognized by science possessing its distinctive horn-shaped structure.

The research team with the University of Malaysia Sabah’s Institute for Tropical Biology and Conservation also says they discovered a new species of fungus that similarly attacks and kills spiders by spreading its invasive spores throughout their bodies before death.

Parasites with Promising Potential

Despite their unsettling parasitic nature, scientists are very intrigued by cordyceps. One reason is that these fungi that can hijack and “zombify” the nervous systems of some insects also possess a range of health benefits when consumed by humans, which include boosting energy and athletic stamina, as well as supporting immune function and helping to reduce inflammation.

“These newly documented fungi hold immense potential,” Seelan told AFP, “both as sources for developing next-generation antimicrobial drugs and as highly effective biocontrol agents against agricultural pests.”

The team’s findings were published in a recent study, titled “Taxonomy and phylogeny of Pleurocordyceps (Polycephalomycetaceae, Hypocreales) associated with ants and cicadas from Malaysia, including a new species and new records,” which appeared in the journal Phytotaxa.

Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.

A surprising discovery inside desert mosses could reshape scientists’ understanding of plant evolution. In some of the driest places on Earth, the ground itself can be alive. What looks like a thin, dark crust on desert soil may actually be a miniature ecosystem, packed with mosses, fungi, bacteria, algae, and tiny animals. These biological soil [...]

Brown rot is a common fungal disease in the Southeastern United States that affects stone fruits like peaches, cherries, and plums. Monilinia fructicola is a tan, fuzzy fungus that grows on tree flowers, twigs, and fruit, and is the most common cause of brown rot. Once brown rot infects a tree, the damage is irreversible, causing significant crop losses in commercial orchards. Farmers try to control the spread of M. fructicola by applying chemical sprays, called fungicides, to fruit trees in the spring.

In M. fructicola, a biosynthesis gene named MfCYP51 encodes a major protein critical to the fungi’s survival. Certain fungicides, called demethylation inhibitor (DMI) fungicides, stop M. fructicola from growing by targeting this protein. Over the last 20 years, DMI fungicides have become less effective against brown rot as M. fructicola becomes more resistant. 

Living microorganisms and their metabolites can control fungal diseases as an alternative to chemical fungicides, known as biofungicides. Many bacteria produce compounds like hydrogen cyanide and pyrrolnitrin that damage fungal cells. However, scientists have not found a biofungicide suitable for commercial production.​ A group of researchers at Clemson University in the USA and Huazhong Agricultural University in China set out to test whether the soil bacteria Pseudomonas chlororaphis and Bacillus subtilis could be effective biofungicides against brown rot. 

The researchers performed an incubation experiment to analyze how the fungal cells make their critical protein from the MfCYP51 gene, a process called gene expression, under different fungicide treatments. They used 3 M. fructicola strains sensitive to traditional DMI fungicides and 3 resistant strains. They tested these with 5 different fungicide treatments: a DMI fungicide, a mixture of P. chlororaphis metabolites, a mixture of living B. subtilis cells, a DMI fungicide + P. chlororaphis metabolites, and a DMI fungicide +  B. subtilis cells. They also set up a control treatment with sterile water instead of fungicide.  

After 6 hours, the researchers extracted the molecule that measures gene expression, called RNA, from the fungi. They found that both the P. chlororaphis treatment and the DMI fungicide + P. chlororaphis treatment substantially reduced MfCYP51 expression in both the sensitive and resistant isolates compared to the controls. In contrast, the DMI fungicide, B. subtilis, and DMI fungicide + B. subtilis treatments increased MfCYP51 expression in the resistant isolates. The researchers concluded that P. chlororaphis has a unique ability to reduce gene expression, unlike other biofungicides.

​To further investigate how the biofungicide treatments work, the team tested whether P. chlororaphis and B. subtilis produced the anti-fungal metabolite pyrrolnitrin. They added 1 milliliter of each treatment to a machine that separates and identifies liquid compounds using high pressure, called a high-performance liquid chromatograph. They found that the P. chlororaphis treatment contained pyrrolnitrin, so they hypothesized that it was responsible for reducing gene expression.

Additionally, the researchers tested their 5 treatments on brown rot in fruit. For each treatment, they took 10 Gala apples, washed and sterilized their surfaces, and sprayed them with the fungicides. After 24 hours, they poked holes in the apples with toothpicks and added 20 microliters of liquid containing M. fructicola cells to the poked holes. They placed the apples in a humid chamber for 5 days and measured the number and size of brown rot spots that developed on their surfaces. 

Despite decreasing MfCYP51 expression, ​the researchers found that P. chlororaphis treatment alone didn’t reduce brown rot disease compared to the control, but the DMI fungicide and B. subtilis treatments did. The mixed treatments of DMI fungicide + P. chlororaphis and DMI fungicide + B. subtilis both reduced brown rot disease compared to the control, but only the DMI fungicide + P. chlororaphis treatment prevented it. 

​The researchers concluded that although biofungicides may not be fully effective on their own, commercializing them could allow farmers to use less DMI fungicide. They explained that scaling back the use of DMI fungicides would slow M. fructicola resistance. Finally, they proposed that future researchers test biofungicide mixtures containing pyrrolnitrin in the field to observe real-world effects on stone fruit trees.

The post Using bacteria to fight fungal brown rot appeared first on Sciworthy.

By studying fungal microfossils in 66-million-year-old rock samples from the Denver Basin in Colorado, Johns Hopkins University microbiologists have confirmed that the dinosaur-killing asteroid impact triggered a worldwide fungal takeover, and uncovered a second, previously unknown ecological crisis just before it.

The post Fungi Bloomed Twice around End-Cretaceous Mass Extinction appeared first on Sci.News: Breaking Science News.