researchers at the BioEnergy Science Center, one of three U.S. Department of
Energy-funded research centers, have partnered to figure out how to break down
plants so that they easily release the simple sugars that can be processed into
biofuels. It’s a breakthrough that could make biofuels cost competitive with
of Georgia researchers who are part of the team have taken an important step
toward that goal by identifying a previously uncharacterized gene that plays a
major role in cell wall development of Arabidopsis plants, a discovery that
promises to help turn plants into biofuel more efficiently.
The team of
researchers found that the gene GXMT1 is responsible for directing a key step
in the development of the plant polymer xylan, a principal component of cell
walls in woody biomass that make it resistant to biofuel conversion.
“Our goal is
to figure out how the plants make this polymer,” says William York, the
study’s principle investigator and faculty member in the UGA Complex
Carbohydrate Research Center. “If we can manipulate that process, we can
change how plants make their cell walls, which could make them easier to turn
into liquid fuel.”
As a member of
the BioEnergy Science Center, York joins multidisciplinary, multi-institutional
research teams pursuing the fundamental scientific breakthroughs needed to make
the production of cellulosic biofuels derived from non-food plant fiber cost
effective on a national scale.
that the problem with many biomass plant candidates is not that they are
difficult to grow or harvest, but that they are difficult to process. In order
to make biofuels, processing facilities use microbes to ferment the naturally
occurring plant sugars into ethanol and other valuable products, much in the
same way distilleries make alcoholic beverages.
But plants have
evolved powerful defenses against the microbes researchers use to break down biomass
for fermentation. This research demonstrates that manipulation of biomass
structure at the molecular level could yield a crop that is more easily
converted into biofuel.
“We want to
develop strains of plants that are strong and grow well but break down easily
when we want them to,” says York, who is also a professor of biochemistry
and molecular biology in the UGA Franklin College of Arts and Sciences and a
member of the UGA Bioenergy Systems Research Institute.
In their paper,
published in the Proceedings of the National Academy of Sciences, the
researchers identified a mutant GXMT1 plant that produces structurally modified
xylan that is more easily released when the biomass is treated with hot water.
The release of xylan during this treatment will ultimately make it easier for
microbes to digest the woody fibers and convert them to ethanol.
can find ways to capitalize on this mutant version of the plant and alter this
gene without compromising the structural integrity of the wood, they can begin
the process of developing plants specifically designed for biofuel conversion.
development of efficient biofuels is a major driving force behind their work,
this research also contributes significantly to the understanding of basic plant
discovery, GXMT1 was categorized in scientific literature as a protein of
unknown function, but it is now the first enzyme shown to catalyze the
formation of methyl-glucuronic acid, a key structural component of xylan in
and his collaborators hope that their research will open the door to new ways
of manipulating plants and making them more useful to humans.
plants for everything: We eat plants, we build our homes out of plants, we make
all sorts of things with them,” York says. “If we can change them, we
can make them easier to work with.”
Source: University of Georgia