In order to delve deeper into how the bacteria works, Dong-Chan Oh, a postdoctoral researcher in Clardy's Harvard Medical School lab, used a variety of laboratory tools, such as nuclear magnetic resonance techniques and chromatography, to both locate the molecule and identify its structure. The molecule turns out to be a kind of fatty acid.
"It's becoming clear that symbiotic relationships between plants, animals, and microbes are essential for the diversification of life and evolution of organisms," says Currie. "This is an example of a system where we have insights into the importance of the diversity of microbes. We believe that this type of mutualism is widespread."
In addition, the researchers suspect that this association represents a source of small molecules that can be used in medicine.
"This molecule is nature's anti-fungal," says Clardy, "and it looks like there are a lot of them."
This is particularly significant, since pathogenic fungal infections in people are a major health concern. These infections are often fatal, and at the moment, no reliable medications for them exist. Here, however, we have an example of an antibiotic successfully disabling a powerful fungi.
"This particular molecule is too unstable to be a viable candidate," says Clardy. "Still, we need to study how it kills fungi, learn the mechanisms. We can look into other bacterial genomes and investigate other anti-fungal processes."
Suspecting that this symbiotic dynamic is far more the rule than the exception, Clardy and Currie are investigating other insect species as well to see how universal this "story arc" is.
|Contact: David Cameron|
Harvard Medical School