Project description:Methanosarcina species are the most metabolically versatile of the methanogenic Archaea and can obtain energy for growth by producing methane via the hydrogenotrophic, acetoclastic or methylotrophic pathways. Methanosarcina barkeri CM1 was isolated from the rumen of a New Zealand Friesian cow grazing a ryegrass/clover pasture, and its genome has been sequenced to provide information on the phylogenetic diversity of rumen methanogens with a view to developing technologies for methane mitigation. The 4.5 Mb chromosome has an average G + C content of 39 %, and encodes 3523 protein-coding genes, but has no plasmid or prophage sequences. The gene content is very similar to that of M. barkeri Fusaro which was isolated from freshwater sediment. CM1 has a full complement of genes for all three methanogenesis pathways, but its genome shows many differences from those of other sequenced rumen methanogens. Consequently strategies to mitigate ruminant methane need to include information on the different methanogens that occur in the rumen.
Project description:Hydrogenases are a critical component of H2-dependent energy-conservation pathways in Methanosarcina barkeri. To allow phenotypic analysis of the hydrogenases, we constructed mutants lacking the frhADGB, freAEGB, vhtGACD, vhxGAC and echABCDEF operons, individually and in all possible combinations. In addition to measuring the effect of each deletion on growth, methane production, and hydrogenase activity, the effect on gene expression was measured by RNA sequencing to detect potential transcriptional regulation by the hydrogenases.
Project description:Global transcriptomics analysis of the Desulfovibrio vulgaris change from syntrophic growth with Methanosarcina barkeri to sulfidogenic metabolism
Project description:Genetic, Biochemical, and Molecular Characterization of Methanosarcina barkeri Mutants Lacking Three Distinct Classes of Hydrogenase
