Environmental metagenomics diagnosing extreme environments, tapping opportunities for clean energy

In his recent State of the Union speech President Bush said technology is the best way to break the nation's addiction to oil. The U.S. Department of Energy Joint Genome Institute (DOE JGI) is directing the technology of DNA sequencing to scan the environment for processes that will lead to cheaper and easier to produce biofuels.

"Through DNA sequencing and the tools of molecular biology we can generate diagnostic fingerprints, Environmental Genomic Tags or EGTs, that provide a metabolic profile of any environment, even such extreme conditions as acid mine drainage," says Edward M. Rubin, DOE JGI Director. "We can then survey this vast catalog of biodiversity and harness the microbial pathways that catalyze the conversion of lignocellulosic feedstocks, such as wood chips, crop residue, and various grasses, into cleaner sources of energy." One of the systems that DOE JGI characterizing is the microbial community inhabiting the termite hindgut, among nature's most efficient bioreactors--capable of generating two liters of hydrogen from fermenting just one sheet of paper.

Rubin will discuss these advances on a panel entitled "Biosphere Monitoring and Ecosystem Forecasts: Sensing the Pulse of the Planet," organized by Stan Wullschleger and Thomas Wilbanks of Oak Ridge National Laboratory, at the American Association for the Advancement of Science (AAAS) Annual Meeting, Friday, February 17 from 8:30 am to 11:30 am, at the Renaissance Hotel, Majestic C, 800 Washington Avenue, St. Louis, MO. The session will also highlight advanced sensing technologies, biosphere monitoring platforms, and ecosystem forecast models for predicting the impacts of climate change. For a full session description, see: http://php.aaas.org/meetings/MPE_01.php?detail=974

"Environmental systems are extremely complex, harboring numerous diverse species coexisting in a single niche," says Rubin. "The challenge is that the vast majority of microbes are resistant to being grown under standard laboratory conditions. Through the emerging strategy of metagenomics--isolating, sequencing, and interpreting the DNA extracted directly from the environment in question, an informative window opens onto that important and underutilized portion of the biosphere.

"Termites eat wood, but they can't extract energy from the complex lignocellulose polymers within it," Rubin says. "These polymers are broken down into simple sugars by fermenting microbes in the termite's gut, using enzymes that produce hydrogen as a byproduct.

"It's not as if we are going to put termites in our tank, but if we can harness the termite microbe enzymes that breakdown lignocellulose and make hydrogen, we may end up with a commercially viable process," says Rubin.

Source : DOE/Joint Genome Institute