Researchers at the Scripps Institution of Oceanography at University of California, San Diego, have made a significant breakthrough in algal biology with implications for biofuels. Algae typically overproduce lipid oils—energy-storing fat molecules used in biofuel production—when they are starved for nutrients, but this starvation also limits their growth and multiplication. The Scripps team was able to metabolically engineer a disruption in fat, reducing enzymes called lipases, to allow for an increase in lipids while maintaining productive growth. Using transcriptomics to guide identification of target lipases in the Thalassiosira pseudonana diatom, the team was able to demonstrate a genetics technique that could have broader implications to other algae species and significantly enhance the productivity of algae, which could lead to improved economics of algal biofuel production.

Low algal biomass yields have been identified as a key driver of the high cost of algae-based biofuels because of the high capital investment projected to achieve commercial-scale volumes. Increased yields achieved by demonstrating radical improvements in lipid content and culture growth will decrease the amount of capital investment needed, better utilize fixed assets, and improve the environmental sustainability of algae-based biofuels.

The report, Metabolic engineering of lipid catabolism increases microalgal lipid accumulation without compromising growth, was published November 18, 2013, in the Proceedings of the National Academy of Sciences of the United States of America.

The Bioenergy Technologies Office (BETO) works with a broad spectrum of industrial, academic, agricultural, and nonprofit partners across the United States to develop and deploy commercially viable, high-performance biofuels, bioproducts, and biopower from renewable biomass resources in America to reduce our dependence on imported oil. 

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