Tobacco Plants Tapped to Suck Up Pond Scum

THE GIST:

• Genetically engineered tobacco plants can suck toxic pond scum out of water.
• The plants get the ability from implanted genes that produce antibodies which bind to toxins.
• The technique could be an efficient way to clean up all sorts of environmental pollutants.

In a British laboratory, tobacco has done some good. With the help of a couple extra genes, it has proven itself capable of disarming a dangerous environmental toxin, called toxic pond scum.

By proving that the principle is possible, engineered tobacco is paving the way for a new generation of plants that could clean up environmental problems -- and do it cheaply.

The tobacco's powers came from implanted genes that produce antibody proteins, which bind to toxins and make them less dangerous.

"This is the first time that plants have been produced to express an antibody to a genuine environmental pollutant," said Pascal Drake, a plant biotechnologist at St. George's University of London. "Particularly a dangerous environmental pollutant."

Pond scum is a type of algae that makes water unsafe for drinking, swimming, fishing or watering crops. It's a big problem in the developing world, Drake said, and algal blooms are becoming more common.

WATCH VIDEO: HowStuffWorks: Gentically modified crops increase efficiency.

Related Links:

• Top 10 Genetically Modified Crops
• Is Tobacco the Next Anti-HIV Weapon?
• HowStuffWorks.com: Tobacco
• Tobacco Plants Tapped to Grow Solar Cells

In 2002, he and colleagues found that genetically engineered plants could produce generic antibody proteins that bind with generic instigator molecules. Next, they wanted to look for real-world applications, and to see if they could get an engineered plant to suck a real toxin out of the environment.

First, the team engineered tobacco plants that produced pond scum antibodies, and they grew the plants in a liquid medium inside lab jars. After adding pond scum to the water, they were able to show that the plants secreted antibodies and that those antibodies latched on to the pond scum toxin.

"Binding to the pollutant might reduce its bioavailability," Drake said. "It might make it less dangerous and less likely to be taken up by animals and humans."

To clean up real polluted waters, scientists would want to use aquatic plants instead of tobacco, which is simply a good plant to work with in the lab. In order to circumvent concerns about GM-plants, Drake added, plants could be engineered to produce antibodies only in their roots, so that edible leaves or fruits wouldn't bind to the toxin. Or, engineered trees could be harvested after they've sucked up pollution but before they've flowered.

"There are ways around these fears that people have," Drake said.

This is not the first time genetically engineered plants have been used to make antibodies, said Neil Bruce, a biologist at the University of York in the United Kingdom. Scientists have been testing the same concept to remediate heavy metals, among other applications. But the new study adds even more evidence that the technique could be a cheap and efficient way to clean up environmental pollutants.

"This is another example of how plants can be engineered to remove toxic materials from the environment," Bruce said. "It's a nice example."