With students caught up in final exams before rushing home for the holidays, odds are some students will return to school in January to find the leftovers in their refrigerators covered in mold. Luckily for them, scientists like David Cane, a professor of chemistry, are hot on the fungi trail. Cane collaborated with labs in France and Spain to identify the sequence of a toxin-producing gene in Botrytis cinerea, or gray mold.
Gray mold is a widespread fungus that kills "both agricultural and ornamental plants" such as roses, cabbage and strawberries, Cane said. The mold poses a significant problem for farmers, Cane added, because it can wipe out an entire crop.
"There is a constant chemical warfare going on between plants and microorganisms," Cane said. Whereas human beings are protected by their immune systems and ability to walk, "plants are really stuck. A plant is a big glob of amino acids and sugar, and it's rooted to the ground."
The international collaboration between Cane and French scientist Muriel Viaud, who have never met in person, first began about a year and a half ago when Cane found a genetic sequence of interest to him in the completed genome of Botrytis cinerea that Viaud had sequenced.
A team in Spain that specializes in the analysis of organic compounds was also involved in the project.
Together, the three labs were able to identify the specific gene cluster in gray mold that produces its plant-killing toxin and demonstrate that deleting the gene from the fungus eliminated its "ability to infect test plants" by stopping toxin production, Cane said.
Cane's lab demonstrated the gene's biochemical function by introducing the sequence into E. coli bacteria and producing a pure version of a protein the mold uses to synthesize its toxin.
The work's collaborative element brought the project to a "level of completeness" that the individual researchers could not have achieved alone, Cane said, because each lab had experts in a different subfield of science.
Cane's role in the project came naturally, he said, because "chemists are very good at answering the question, how does this work?"
Although the identification of the gene implicated in gray mold's toxin production was an important breakthrough, the discovery is "a long way away from commercial application," Cane said.
Still, "if you understand how a toxin is made, that gives you a number of potential tools for inhibiting its function," he said, adding that an agricultural product designed to fight gray mold would need to be cheap and non-toxic.
"If it costs you $50 to protect a $3 basket of strawberries, you are not going to (buy such a product)."