ABERDEEN, England, April 7 (UPI) -- Human fungal infections are already known to cause sickness, tissue damage and even death in humans, however scientists have not understood the toxins a fungus uses to infect a host until now, according to a new study.
Researchers in England made the discovery while studying how human oral cells respond to fungal infections, and suggest the knowledge will help treat patients who acquire the infections in the future.
The toxin was identified in Candida albicans, a yeast that lives in the gut and causes disease such as thrush. Infections by the fungus, often in the mouth, can occur in very young and very old people, as well as HIV patients and others with weakened immune systems.
Most pathogenic fungi don't damage their hosts, the researchers said, which led them to look more closely for those that do, and how they do it.
For the study, published in the journal Nature, researchers looked more closely at the interactions between Candida albicans and human oral cell samples.
They found Candida albicans produces a polypeptide, a larger molecule than would be expected for a toxin, which is then divided into small pieces inside the fungus, and just one of the pieces is the toxin, which the researchers named Candidalysin.
"This is an important observation," Duncan Wilson, a researcher at the University of Aberdeen, said in a press release, "because it finally provides a molecular explanation to a question that has puzzled the field for decades: Why are hyphae the virulent morphology of Candida albicans?"
Researchers said it has taken decades to figure this out, partially because newer technology and recent research aided their quest, but also because the toxin is only produced when the fungus is infecting a host -- which they could not witness live until now.
Future research will likely focus on how the toxin interacts with the immune system, how it affects the body and the rest of the process for fungal infection by the pathogen, the researchers said.