Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more.
It’s not every day that effective fungus-killing compounds are discovered, so researchers in Germany knew their recent find needed a special name. Identifying and testing three natural compounds that proved lethal to fungi, they were so impressed they’ve named the chemicals after actor Keanu Reeves, a nod to how he eliminates villains in movies such as “John Wick” and “The Matrix.”
The potential treatment for fungi comes at a time when the organisms are becoming more and more resistant to known antifungals, according to study coauthor Sebastian Götze, a researcher with Germany’s Leibniz Institute for Natural Product Research and Infection Biology. Not only are the newly named microbes effective against plants, researchers found the compounds — molecules commonly found in bacteria called lipopeptides — also to be an effective treatment against human fungal infections.
The study was published recently in the Journal of the American Chemical Society.
“The lipopeptides kill so efficiently that we named them after Keanu Reeves because he, too, is extremely deadly in his roles,” Götze said in a statement.
“We have a crisis in anti-infectives. … Many human-pathogenic fungi are now resistant to antimycotics (antifungals) — partly because they are used in large quantities in agricultural fields.”
Called “keanumycins,” the newly found antimicrobial compounds are a natural byproduct of the bacteria Pseudomonas typically found in soil and water. Researchers came across the compounds when studying Pseudomonas for their effectiveness against predatory amoebas.
Scientists have known that “many of these bacterial species (Pseudomonas) are very toxic to amoebae, which feed on bacteria,” said lead study author Pierre Stallforth, head of the department of paleobiotechnology at the Leibniz Institute, in a statement. Stallforth and his fellow researchers wanted to explore the bacteria’s effectiveness against fungi, which have a cell structure similar to that of amoebas, according to the study.
Researchers initially tested keanumycins A, B and C on a hydrangea that had been infected with Botrytis cinerea, a plant pest better known as the trigger for gray mold rot. The fungus commonly infects certain fruits and vegetables and causes collateral damage to harvests.
The compounds are biodegradable, according to the study, and could provide an environmentally friendly alternative to pesticides in efforts to save food supply.
Further testing also showed that the keanumycins are effective against Candida albicans, a natural yeast that’s typically found in the human microbiome but can overgrow and turn into a severe infection.
Fungal infections have been a hot topic recently due to HBO’s “The Last of Us,” and as the show suggests, the conditions can be difficult to treat but not impossible. (HBO, like CNN, is a unit of Warner Bros. Discovery.) Testing of the keanumycins has shown that the compounds are not especially harmful and toxic to human cells, a problem often seen in the development of antifungal treatments since fungal cells share similar properties with animal cells.
“This study documents another exciting means by which microbes have evolved to compete with and fight other organisms,” said Dr. Matt Nelsen, a researcher from Chicago’s Field Museum, in an email.
“Previous efforts have sought to exploit such natural products for human use to combat animal and plant pathogens,” Nelsen added. “However, over time, many pathogenic organisms — including fungi — have evolved resistance to the chemicals we use to battle them. Consequently, we need to find a new way to ‘outsmart’ or ‘one-up’ them.”
Keanumycins are “good lead structure candidates for the development of antifungal drugs,” according to the study, and could be a new treatment option in an area where they are “desperately needed.” Researchers said they will be carrying out further testing on the compounds.
“One means by which organisms engage in this battle (competition with other organisms) is through the synthesis of chemicals that may inhibit the growth of or kill other organisms,” Nelsen said. With further research, it will be exciting to understand how widespread keanumycins are, Nelsen added, and to see how many other species in the Pseudomonas genus can produce these compounds.