The enzyme has been characterized from several archaeal species. In the methanogenic archaeon Methermicoccus shengliensis the enzyme participates in methanogenesis from methoxylated aromatic compounds, while in the non-methanogenic Archaeoglobus fulgidus it participates in methoxydotrophic growth. The enzyme catalyses the transfer of a methyl group bound to the cobalt cofactor of a dedicated corrinoid protein (MtoC) to tetrahydromethanopterin or tetrahydrosarcinapterin. cf. EC 126.96.36.1995, [methyl-Co(III) methoxylated-aromatic-compound-specific corrinoid protein]---tetrahydrofolate methyltransferase.