"If we're not using that cropland to make cigarettes anymore, then perhaps we could use it to make enzymes," says Beth Ahner, Professor of biological and environmental engineering at Cornell's College of Agriculture and Life Sciences. Ahner is discussing a new study led by Cornell University in collaboration with the University of Illinois, in which scientists have successfully reared genetically engineered tobacco plants to produce medical and industrial proteins outdoors in the field. Their findings are published in the journal Nature Plants.
"We knew these plants grew well in the greenhouse, but we just never had the opportunity to test them out in the field," adds Ahner. According to the researchers, the study opens doors to growing genetically engineered plants on a large scale, which, considering that the market for biologically derived proteins is predicted to reach $300 billion in the near future, is highly beneficial.
Growing a genetically modified organism outside of the laboratory carries ethical and legal implications, meaning plant biology Professor Stephen Long from the University of Illinois had to seek approval from the U.S Department of Agriculture to run the study.
The researchers engineered the plants to produce functional proteins, such as enzymes, that are not native to the plant itself. These proteins have a wide range of applications, in the agricultural, food, and the medical industry.
Current approaches to manufacturing industrial enzymes and proteins involve large, expensive fermenting reactors. Growing the plants outdoors could reduce the cost of production by two-thirds.
Are tobacco plants up to the challenge?
It could be assumed that asking a plant to convert 20 percent of its proteins into material that is essentially of no use to it would burden growth. Interestingly, this was not what the researchers found: "When you put plants in the field, they have to face large transitions, in terms of drought or temperature or light, and they're going to need all the protein that they have," Ahner notes. "But we show that the plant still is able to function perfectly normally in the field [while producing non-native proteins]. That was really the breakthrough."
Jennifer Schmidt, a graduate student in Ahner's lab, adds: "Transforming tobacco plants is going to be a simpler and cheaper solution, where once we know it works, all you have to do is grow a field of plants and harvest them like normal tobacco."
"This represents a new strategy for us to be able to make enzymes either for agricultural applications, for food additive applications, or for consumer applications, in a way that is very cheap and very safe," Ahner concludes.