New Clues to Cold Tolerance and Lipid Production for Biofuels in Polar Alga

Optimal growth temperature and global amino acid composition indicate that C-169 is not fully specialized to grow in a permanent cold environment.

The Science

Algae are of major interest to researchers who are developing alternative energy sources. For example, lipids making up algal membranes can be transformed into biodiesel. One photosynthetic alga, Coccomyxa subellipsoidea C-169, was recently isolated in Antarctica and now is the first alga from a polar region to have its genome sequenced. Surprisingly, the alga thrives at temperatures close to 20°C, though it is tolerant of the cold temperatures in the Antarctic. C. subellipsoidea was sequenced by the DOE Joint Genome Institute, and its predicted protein families were compared with those from several other sequenced green algae. The researchers found that the polar alga had more enzymes involved in lipid metabolism, such as those that desaturate fatty acids. This greater versatility of lipid metabolism is thought to have contributed to its adaptation to cold. The research will provide insights on novel enzymes that may prove useful to researchers working to harness algae for biodiesel production.

Summary

Little is known about the mechanisms of adaptation of life to the extreme environmental conditions encountered in polar regions. Here researchers present the genome sequence of a unicellular green alga from the division chlorophyta, Coccomyxa subellipsoidea C-169, hereafter referred to as C-169. This is the first eukaryotic microorganism from a polar environment to have its genome sequenced.

Principal Investigator

Guillaume Blanc
Aix-Marseille University

BER Program Manager

Ramana Madupu

U.S. Department of Energy, Biological and Environmental Research (SC-33)
Biological Systems Science Division
[email protected]

References

Blanc, G., I. Agarkova, J. Grimwood, A. Kuo, A. Brueggeman, D. D. Dunigan, J. Gurnon, I. Ladunga, E. Lindquist, S. Lucas, J. Pangilinan, T. Pröschold, A. Salamov, J. Schmutz, D. Weeks, T. Yamada, A. Lomsadze, M. Borodovsky, J.-M. Claverie, I. V. Grigoriev, and J. L. Van Etten. 2012. “The Genome of the Polar Eukaryotic Microalga Coccomyxa subellipsoidea Reveals Traits of Cold Adaptation,” Genome Biology 13, R39. DOI: 10.1186/gb-2012-13-5-r39.