Breaking down organic wastes typically involves microbial communities of bacteria and archaea working in concert with methanogens, which remove the hydrogen generated during the degradation process.
The interactions between these syntrophic communities are being studied to understand the roles these microbes play individually and and as whole. In the August 2010 issue of the journal Environmental Microbiology, a team of researchers including the DOE JGI’s David Sims, Cliff Han, Edwin Kim, Thanos Lykidis and Alla Lapidus studied the bacterium Syntrophomonas wolfei subsp. wolfei str. Gottingen, the only microbe known to break down fatty acids four to eight carbons in length anaerobically.
|The methanogen S. wolfei’s ability to generate biohydrogen could help researchers develop renewable, clean energy sources. (Image courtesy of Mike McInerney)
Sequenced at the DOE JGI using the whole-genome shotgun (Sanger) method, the 2.94-million base pair genome was finished at Los Alamos National Laboratory in 2006. S. wolfei produces hydrogen and methane as byproducts materials could be used for producing clean-burning fuels or used in fuel cells. As S. wolfei is being used the model microorganism for studying syntrophic fatty acid metabolism, the genome gives researchers insights to develop technology for harnessing biohydrogen for a renewable energy source. Another question the researchers hope to better understand “how organisms conserve energy and grow when the thermodynamic driving force is very low.”