Up close, some species of fungi look like beautiful, but alien lifeforms. Neither plant nor animal — they're a kingdom of life all on their own.
These bizarre, yet fundamental forms of life are explored in a new documentary, The Kingdom: How Fungi Made Our World (airs on CBC TV's The Nature of Things on Sunday, April 8 at 8 p.m., 8:30 p.m. NT).
As explored in the documentary, directed by Annamaria Talasfungi, fungi are key to humanity's survival, from antibiotics to the fortification of beer — but are also potential threats as the planet's temperature rises.
"Humans are lucky in that we have a core body temperature which is higher than the vast majority of fungi are able to grow at," explains Karen Bartlett, a microbiologist at the University of British Columbia, who is featured in the documentary. "The fungal 'threats' have actually always been around, but we are seeing a rise in more susceptible populations, and hence are more aware of the possibility of fungal infections."
Bartlett is an expert on a yeast family called Cryptococcus gattii, a microscopic fungus that is normally found in tropical zones, but can now be found on Vancouver Island. The fungus has affected cats and dogs and people with a suppressed immune system.
The fungus is not likely to become a killer epidemic, however.
"For instance, back in the 1980’s when the HIV virus was causing a severe immunosuppression resulting in AIDS, we 'suddenly' saw an increase in the number of AIDS patients with potentially fatal fungal infections," Bartlett says. "The fungal species involved weren’t new, but having a bigger population of immunosuppressed people meant that there was more chance that laypeople, relatives and friends, as well as health care workers. were seeing or hearing the fungal names more often. For the vast majority of people, it is simply a functioning immune system is what protects us from most systemic fungal infections."
So how did a tropical fungus like this end up on Vancouver Island?
"We do think there was a relationship between changing land use patterns and warmer, drier weather patterns that resulted in more exposure, and the exposure was to a susceptible population," she says. "But that’s not to say that C. gattii will suddenly be everywhere like an alien invader. There is still a strong environmental niche that is associated with C. gattii, and it is not spread person to person.
"We will be seeing more fungal disease in humans in future, but we won’t be seeing fungal disease as sudden epidemics like we see with influenza."
As the documentary explores, fungi have been key to the survival of humanity.
“Fungi are fascinating, we have co-evolved with fungi and [they] will be here long after humans have blown themselves off the face of the Earth.” says Bartlett. “We have exploited fungi for antibiotics, enzymes, and methods of food preservation. Fungi have fostered human evolution by providing the building blocks for making bread, wine and beer.”
For instance, ten of the top 20 modern day antibiotics are derived from various fungi.
Of course, there's bad news there, too, as many diseases are becoming resistant to antibiotics.
Fungi may be our friend here, though, as McMaster University biochemist Gerry Wright, helped discover. In the documentary, he discusses Aspergillomarasmine A, which could maybe one day boost the effectiveness of existing antibiotics.