This project will involve the construction of metagenomic libraries from the microbiome resident in the foregut of the tammar wallaby (Macropus eugenii), a marsupial unique to Australia and New Zealand. The foregut microbiome of these animals coordinates efficient plant biomass degradation, but unlike that in ruminants and other herbivorous vertebrates, anaerobic fermentation in wallabies results in relatively low methane emissions. For these reasons, we propose that functional and comparative studies of the foregut microbiome of the tammar wallaby relative to other gut microbiomes (e.g., ruminants and termites) will provide novel science and understanding of plant biomass degradation, carbon sequestration, and hydrogen utilization.
This project addresses the DOE mission and strategic goal of using world-class scientific research and knowledge to provide a reliable and affordable supply of environmentally sound energy. We and our collaborators seek to discover in nature novel microorganisms and associated biochemical processes that are responsible for efficient conversion of plant biomass (lignocellulose) to useful metabolites. These metabolites can then be used to generate fuels and chemicals that are “environmentally cleaner” than fossil fuels. Hydrolysis of lignocellulose is generally considered as the rate-limiting step in the overall conversion of plant biomass to biofuels. A refined understanding of the microorganisms and pathways directly involved in lignocellulose hydrolysis and hydrogen production in the absence of methanogenesis may lead to alternative industrial processes of biofuel generation.
This approach complements existing activities (which focus on available enzymes that are thought to require considerable investment of time and effort for improvement) by screening the vast and untapped genetic resources present in uncultivatable microorganisms. Additionally, the suite of enzymes that will be identified via metagenomics may play a key role in the development of new feedstock sources such as agricultural wastes and perennial energy crops that are more amenable to rapid and extensive deconstruction.
Principal Investigators: Chris McSweeney (CSIRO), Mark Morrison (Ohio State Univ.), Evelyne Forano (INRA, France), Joël Doré (INRA, France), and Phillip Hugenholtz (JGI).