Considered the second most important greenhouse gas, methane is 21 times more potent than carbon dioxide. Methane-oxidizing bacteria called methanotrophs help reduce levels of atmospheric methane.
To better understand the bacteria involved in the global methane cycle, the DOE JGI sequenced, assembled and annotated the genome of Methylosinus trichosporium OB3b.
The project was led by DOE JGI collaborator Lisa Stein from the University of Alberta, who proposed that the bacterium be a 2008 Community Sequencing Program (CSP) project, and involved several DOE JGI including Lynne Goodwin, Loren Hauser and Microbial Program head Tanja Woyke.
|Methane-oxidizing bacteria (Methylosinus trichosporium OB3b) cluster on copper-doped glass. (Cover image from the July 17, 2007 issue of Proc. Natl. Acad. Sci. USA by Ezra Kulczycki.)|
Originally isolated in 1970, the bacterium has been extensively studied to identify and characterize several key enzymes involved in methane oxidation. For example, one enzyme is crucial to M. trichosporium’s ability to use copper in order to efficiently oxidize methane, a mechanism that significantly impacts global methane oxidation patterns. The 4.8-million base pair draft genome was sequenced using Roche 454 and Illumina machines. Aside from genes involved in methane oxidation, genes involved in nitrogen fixation and ammonia transport were also identified.
Other DOE JGI researchers who co-authored the study were David Bruce, Jan-Fang Cheng, Alex Copeland, Cliff Han, Miriam Land, Alla Lapidus (now at the Fox Chase Cancer Center), Susan Lucas and Sam Pitluck.