methanobrevibacter thaueri methanobrevibacter thaueri methanobrevibacter thaueri is a species of methanogen archaeon, named after rolf k. thauer. methanobrevibacter thaueri scientific classification domain: archaea kingdom: euryarchaeota phylum: euryarchaeota class: methanobacteria order: methanobacteriales family: methanobacteriaceae genus: methanobrevibacter species: m. thauerimiller and lin, 2002 description coccobacillus with slightly tapered ends, about 0.5 micrometres in width and 0.6-1.2 micrometres in length, occurring in pairs or short chains. gram-positive reaction. its cell walls are composed of pseudomurein. it is a strict anaerobe and its type strain is cwt (=dsm 11995t =ocm 817t). it was first isolated from cow faeces.