Genetically Engineered Duckweed As Potential Biofuel Source

Duckweed, a common aquatic plant, was the latest interest for innovation by scientists from the United States Department of Energy's Brookhaven National Laboratory and the Cold Spring Harbor Laboratory who thought of engineering the plant to produce high yields of oil that can be harvested to produce biofuels and other bioproducts.

The scientists thought of duckweed considering how fast it grows and most of the plant's biomass is in its leaf-like fronds that grow on the surface of ponds. The collaborative project brought together the two expertise in the biochemistry and regulation of plant oil biosynthesis and the cutting-edge genomics and genetics capabilities. One of the oil-production genes identified by the Brookhaven researchers pushes the production of fatty acids. Another pulls, or assembles, the fatty acids into molecules called triacylglycerols (TAGs). The third gene produces a protein that coats oil droplets in plant tissues, protecting them from degradation. The engineered duckweed with all three modifications was found to have accumulated up to 16 percent of their dry weight as fatty acids and 8.7 percent as oil when results were averaged across several different transgenic lines.

The scientists intend to focus on testing the push, pull, and protect factors from different sources to enhance the levels of the three genes' oil-inducing expression and refine the timing of the expression. Once optimized, the engineered duckweed can be grown and harvested in batches and extracting its oil could be an efficient pathway to renewable and sustainable oil production without having to compete with crops for land use.

Learn more from AAAS's EurekAlert! and the Plant Biotechnology Journal.