Image courtesy of B. Boonyaratanakornkit, D.S. Clark, G. Vrdoljak, University of California, Berkeley
Scanning electron micrograph of the first sequenced archea Methanococcus jannaschii.
A partnership between a methanogenic archea and sulfate reducing bacteria results in a substantial shift in genes in the methanogen associated with conversion of hydrogen to methane and a switch to a parallel set of enzymes that may be better adapted to low rates of hydrogen production.
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.
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.
Dr. Aindrila Mukhopadhyay
Lawrence Berkeley National Laboratory
Basic Research: DOE Office of Science, Office of Biological and Environmental Research
Christopher B Walker, Alyssa M Redding-Johanson, Edward E Baidoo, Lara Rajeev, Zhili He, Erik L Hendrickson, Marcin P Joachimiak, Sergey Stolyar, Adam P Arkin, John A Leigh, Jizhong Zhou, Jay D Keasling, Aindrila Mukhopadhyay and David A Stahl. 2012. “Functional responses of methanogenic archaea to syntrophic growth” ISME Journal [DOI:10.1038/ismej.2012.60]
University, DOE Laboratory