Isolation and characterization of a new thermophilic Methanosarcina strain (strain MP).

A thermophilic Methanosarcina strain was isolated from a digester fed with water hyacinths and inoculated with ground termites from the Congo. Optimal growth temperature was 55 degrees C. Methane production was at its optimum between pH 6.5 and 7.0. The bacterium grew on acetate, methanol and methylamines in the absence of growth factors, but could not use H2-CO2 or formate. H2-CO2 inhibited acetate utilisation. Yeast extract and vitamins stimulated growth.