Scientists engineer faster-growing trees ideal for biofuel

ATHENS, Ga., March 19 (UPI) -- Most genetic manipulation efforts have been trained on cash crops and flowers, but trees are big business too, and designing them to work better for what the market demands is important work.

Scientists at the University of Georgia recently showed that the manipulation of a single gene in a hardwood tree species makes it grow faster and break down into fuel more easily.

The growth rate increase was a surprise. Researchers at Georgia were focused on weakening the species' defenses to enzymes and chemicals used to draw out the sugars used to create biofuels. They were able to zero in on a gene called GAUT12.1, which reduces xylan and pectin production, important components of the protective cell walls in plants.

"This research gives us important clues about the genes that control plant structures and how we can manipulate them to our advantage," study co-author Debra Mohnen, a professor of biochemistry and molecular biology at Georgia, explained in a press release.

"The difficulty of breaking down the complicated plant cell wall is a major obstacle to the cost-effective production of biofuels, and this discovery may pave the way for new techniques that make that process more economically viable," Mohnen added.

In the lab, researchers engineered 11 transgenic trees, with genomic presence of GAUT12.1 diminished by approximately 50 percent.

"Our experiments show that the trees we created were less recalcitrant, meaning that it would be easier to extract sugars from the plant cell walls," said lead study author Ajaya Biswal, an assistant research scientist in Mohnen's lab. "But we were particularly happy to see how quickly these trees grew compared to what one would observe in with the wild type."

The trees grew especially fast. Eastern cottonwoods, the employed species, are already prized for their rapid growth. The transgenic trees matured even faster -- boasting a 12 to 52 percent increase in height and a 12 to 44 percent increase in diameter when compared to the control group.

"We've already learned a lot from this process, but we are confident that we can expand and improve on our research to achieve even better biomass and understanding of how it is produced," Mohnen concluded.

The study was published recently in the journal Biotechnology for Biofuels.