methyl-Co(III)-[tetramethylammonium-specific corrinoid protein] + coenzyme M <=> Co(I)-[tetramethylammonium-specific corrinoid protein] + methyl-coenzyme M + H(+)
methyl-co(iii)-[tetramethylammonium-specific corrinoid protein] + coenzyme m <=> co(i)-[tetramethylammonium-specific corrinoid protein] + methyl-coenzyme m + h(+)