When it comes to symbiosis, two is company; three is a crowd. It’s the same thing in nature. The symbiosis between a microbe which provides nutrients and a fungus, which provides a place to live have been a textbook example for the past 150 years. However, it is not the complete story.
Now, a third element was added to the symbiosis. Recent studies have revealed that this third member of the symbiosis is also a fungus, previously unknown to scientists. The fungus has been found on all continents, and its presence shows it is encountered everywhere. It has been part of the symbiosis from the start of this partnership’s evolution.
Catharine Aime, from Purdue University, who co-authored the study believes that textbooks will have to be rewritten.
Toby Spribille, the leader of the novel analysis, has been passionate about lichens for the better part of his life. These lichens are very hard to grow in laboratory conditions. Scientists had no idea how to bring about the symbiosis which happens in nature. So far, experiments on lichens have been few and the results – unsatisfying.
As science advanced, so did metagenomics – DNA extracting tools – have. This type of approach sparked Spribille’s imagination. He found out that a type of lichen encountered in Canada and throughout the western part of the United States called Bryoria had a strong cultural bond with old local tribes. Amerindians used them to get through the winter. They would wash Bryoria of other substances found on their surface so that they wouldn’t get sick.
Part of these substances is a toxic acid, called vulpinic acid. There are two types of Bryoria, one which produces vulpinic acid and is toxic, and the other one which does not.
Laboratory analyses confirmed Spribille’s theories. Now we know a third fungus is a partner in the symbiosis. He used metagenomics, a new scientific method of DNA sequencing, to confirm his findings.
The new fungus is now being studied more intensively. The vulpinic acid is sure to play a role in this symbiosis; scientists are now trying to figure out which. For now, experts believe it produces metabolites, but further research is needed.
Spiribille is amazed at how complex this symbiosis is. He finds a lot of his inspiration in nature.
Image Source – Wikipedia