06/28/2012
Understanding How Microbes Work Together: Methane Production by Partnered Microbes
The Science
Methanogenic archaea and sulfate-reducing bacteria (SRBs) both play important roles in the carbon cycle of soils, wetlands, and other environments with limited oxygen availability. SRBs are versatile consumers of a variety of organic compounds, while methanogens primarily convert hydrogen and CO2 into methane. Neither of these organisms is capable of independent growth on lactate, a small organic compound that is an important intermediate in food webs, but can consume it when working together in a partnership called syntrophy. Researchers at the University of Washington and Lawrence Berkeley National Laboratory have published a new study that helps explain how this partnership works. They carried out a high-resolution transcriptomic study of changes in gene expression of the methanogen Methaococcus maripaludis during syntrophic growth on lactate with the SRB Desulfovibrio vulgaris as a partner. The methanogen shows a substantial shift in genes associated with conversion of hydrogen to methane, switching over to a parallel set of enzymes that may be better adapted to low rates of hydrogen production and other conditions associated with syntrophy. These results advance our understanding of microbial production of a potent greenhouse gas and highlight the important role of subtle interactions between organisms that influence environmental processes.
BER Program Manager
Dawn Adin
U.S. Department of Energy, Biological and Environmental Research (SC-33)
Biological Systems Science Division
[email protected]
References
Walker, C. B., A. M. Redding-Johanson, E. E. Baidoo, L. Rajeev, Z. He, E. L. Hendrickson, M. P. Joachimiak, S. Stolyar, A. P. Arkin, J. A. Leigh, J. Zhou, J. D. Keasling, A. Mukhopadhyay, and D. A. Stahl. 2012. “Functional Responses of Methanogenic Archaea to Syntrophic Growth,” The ISME Journal 6, 2045–55. DOI: 10.1038/ismej.2012.60.