Fungus farmers show way to new drugs
In the quest for new and more effective antibiotics, scientists are turning to ants, in particular leaf cutter ants. These little insects cultivate fungi for food in their colonies.
When researchers at the U. of Toronto investigated how the fungus gardens were protected against destruction, they discovered that the ants carried bacteria that produce an antibiotic that kills off the parasitic fungus that would feast on the fungi. Recently, the same antibiotic was shown to be effective in controling the growth of drug resistant Candida Albicans which causes yeast infections.
In a mutually beneficial symbiosis, leaf-cutting ants cultivate fungus gardens, providing both a safe home for the fungi and a food source for the ants. But this 50-million-year-old relationship also includes microbes that new research shows could help speed the quest to develop better antibiotics and biofuels
Because distinct ant species cultivate different fungal crops, which in turn fall prey to specialized parasites, researchers hope that they will learn how to make better antibiotics by studying how the bacteria have adapted to fight the parasite in an ancient evolutionary arms race. "These ants are walking pharmaceutical factories," says Currie, now at the University of Wisconsin, Madison.
There is also some promise in the biofuels area. Studies are now underway to find out how the ants, bacteria and fungi interact to break down cellulose. Cellulose is a carbohydrate found in plants and is notoriously hard to break down. If an easy way to break it down could be found, then biofuels could be made from sources other than those high in sugars which are comparatively easy to break down.
This research underlines the interaction of many organisms that make up a system. Often insignificant organisms are integral to the system working and the loss of one member of the chorus disrupts all.