Methanogenesis from acetate: a comparison of the acetate metabolism in Methanothrix soehngenii and Methanosarcina spp. FEMS Microbiol Lett 88:181–198. http://dx.doi.org

Acetate is the precursor of approximately two-thirds of the methane prcduced in anaerobic bioreactors. Only two genera of methanogenic archae are known to use acetate as sole energy source: Methanosarcina nd Methanothrix. Meth-anosarcina ppears to be a generalist with a high growth rate, but low affinity for acetate. Methan-othrix is a specialist having a high affinity for acetate, but low growth rate. Methanothrix shows a much lower minimum threshold for acetate utilization (7-70 ~M) than Methar, osarcina (0.2-1.2 raM). This is consistent with the evidence that Methanothri ¢ is found in environments with low acetate concentrations. The acetate degradation by acetotrophic meth-anogens tarts with an activation of acetate t