Reaction catalyzed by methylated-thiol-coenzyme M methyltransferase (2.1.1.251)

		+		a [Co(I) methylated-thiol-specific corrinoid protein]	=		a [methyl-Co(III) methylated-thiol-specific corrinoid protein]	+		hydrogen sulfide
	methanethiol	+		a [Co(I) methylated-thiol-specific corrinoid protein]	=		a [methyl-Co(III) methylated-thiol-specific corrinoid protein]	+		hydrogen sulfide