The enzyme, which catalyses the transfer of a methyl group from dimethylamine to a dimethylamine-specific corrinoid protein (MtbC), is involved in methanogenesis from dimethylamine. The enzyme contains the unusual amino acid pyrrolysine . Methylation of the corrinoid protein requires the central cobalt to be in the Co(I) state. During methylation the cobalt is oxidized to the Co(III) state. The methylated corrinoid protein is substrate for EC 18.104.22.168, methylated methylamine-specific corrinoid protein:coenzyme M methyltransferase.