Scientist wins award
for plant research
By Brian Jackson

OTTAWA — Susan Aitken's found a way to turn corn into a toxic-sucking vacuum.

Faraz Quazi, an undergraduate student in Susan Aitken's lab, helps with her sulfur amino acid research. Aitken has seven students in her lab.

The Carleton University professor of Biology and Biochemistry won a $10,000 Petro-Canada Young Innovator Award for her research in phytoremediation — a process where by plants can soak up heavy metals.

The cash will be put towards her research in that area, but it is just one of the applications where Aitken’s science has potential. In addition to cleaning up contaminated sites, Aitken is looking into methods of growing more nutritious legume crops. She is also researching treatment for heart disease.

Aitken has discovered this array of applications by studying sulfur amino acid regulation. Sulfur molecules are created by enzymes in every living thing, from microorganisms, to plants, to humans.

In plants, amino acids carrying more sulfur molecules boost protein levels to protect from toxicity. However, in humans, high levels have been linked to heart disease.

Aitken applied for this award focusing on her environmental clean-up efforts because she figured Petro-Canada would be interested.

"They’re a refining company, so they care about the image they’re portraying," Aitken says. "They might be more interested in funding a project that helps to clean the environment."

The plants that clean

The process of cleaning contaminated sites using plants is called phytoremediation. Some plants have the natural ability to soak up toxins from the soil, so they can be planted, left to grow, then uprooted and destroyed – presto, the site is clean. But relying on nature to supply these fickle plants won’t cut it, says Aitken.

"Some plants are specifically adapted to different sites, so some plants will take up cadmium but not copper, some take up zinc but not nickel," she says.

Plants that do soak up metals well tend not to grow very large or very fast – they’re no pumpkins.

"Corn grows quite large, quickly over the summer, so it could take up a lot of metals from the ground, then we can harvest it and incinerate it," Aitken says.

Though she is speaking hypothetically, an agricultural crop wouldn’t be used because of the risk of having it accidentally harvested for human consumption.

Instead, Aitken wants to give nonagricultural plants the ability to act like a toxic sponge.

"We want to understand how plants are able to do it," Aitken says. "Then we can transfer that ability to other plants."

Research continues to grow

Aitken’s just beginning to figure out how this might be done. Whether through traditional plant breeding or even genetic engineering, transferring the toxic vacuum ability is a long-term goal.

With the award money, Aitken plans to buy a machine that will process plant samples taken from the Carleton greenhouses in the Nesbitt Biology Building.

"When we take a plant sample, we have to grind them into different buffers to see how much metal they’ve absorbed," Aitken explains. The machine will make things "much less manual and laborious."

After the molecules of a plant are neatly sorted by the machine, they can be examined. Aitken even plans to bring another student on board the project.

After being at Carleton for two years, Aitken is now moving towards the other research goals she feels are important. Her environmental conscience motivates the phytoremediation work.

"Its an environmentally relevant question, there are a lot of contaminated sites in Canada,” Aitken says. “It is reaching the point where we really have to wake up and take notice of this."