NEW YORK (GenomeWeb News) – Researchers have for the first time analyzed a complete genome sequence of a tree, the poplar, which they claim could help develop biofuels.
The research into the tree, also called the black cottonwood or Populus trichocarpa, will appear in tomorrow's edition of Science and “lays the groundwork that may lead to the development of trees as an ideal ‘feedstock’ for a new generation of biofuels such as cellulosic ethanol,” according to a statement released yesterday by the Department of Energy’s Joint Genome Institute. The release was embargoed until this afternoon.
The study identified 93 genes associated with the production of cellulose, hemicellulose, and lignin, which can be turned into biofuels components.
For example, cellulose and hemicellulose, which “constitute the most abundant organic materials on earth,” can be broken down into sugars, fermented into alcohol, and distilled to yield “fuel-quality ethanol and other liquid fuels.”
Researchers performing the analysis identified more than 45,000 protein-coding genes, more than any other organism sequenced to date and approximately twice as many as in the human genome, JGI said.
JGI said the poplar is the “most complex genome to be sequenced and assembled by a single public sequencing facility” and the third plant to date to have its genome completely sequenced and published. Arabidopsis thaliana was the first, followed by rice.
Researchers targeted the poplar as a “model crop for biofuels production” because of its “extraordinarily rapid growth” and because of its “relatively compact” genome, which, at 480 million bases, is 40 times smaller than the genome of pine.
JGI said that "under optimal conditions” poplars can grow 12 feet each year and reach maturity in as few as four years. This would “permit selective breeding for large-scale sustainable plantation forestry” which, “when coupled with conversion of the lignocellulosic portion of the plant to ethanol, has the potential to provide a renewable energy resource along with a reduction of greenhouse gases."
"Fine-tuning plants for biofuels production is one of the keys to making biofuels economically viable and cost-effective,” DOE's Under Secretary for Science Raymond Orbach said in the statement. “This research, employing the latest genomic technologies, is an important step on the road to developing practical, biologically based substitutes for gasoline and other fossil fuels."
DOE scientists “envision a future where vast poplar farms in regions such as the Pacific Northwest, the upper Midwest, and portions of the southeastern US could provide a steady supply of tree biomass rich in cellulose that can be transformed by specialized biorefineries into fuels like ethanol,” the agency said in the statement.
The poplar project is part of a broader DOE plan to accelerate research into biofuels production. As GenomeWeb News reported last month, the DOE and the Department of Agriculture jointly awarded nine grants totaling $5.7 million for biobased fuels research, and the DOE said it would spend $250 million over the next few years to help create two bioenergy research centers that will use systems biology and other methodologies to develop better biofuels.
In July, the DOE said it will enlist university researchers to help its Genomics: GTL program improve ways to develop alternative energy sources after issuing a detailed roadmap disclosing how GTL will participate in a DOE initiative to develop cellulose-based ethanol.
Secretary of Energy Samuel Bodman has set a departmental goal of replacing 30 percent of current transportation fuel demand with biofuels by 2030.
The poplar project took four years led by the JGI and Oak Ridge National Laboratory, “uniting the efforts” of 34 institutions from around the world, including the University of British Columbia, and Genome Canada; Umeå University, Sweden; and Ghent University, Belgium.