. "\"Catalysis of the reaction: (6S)-5-methyl-5,6,7,8-tetrahydrofolate + L-homocysteine = (6S)-5,6,7,8-tetrahydrofolate + L-methionine.\" [EC:2.1.1.13, RHEA:11175]" . . "methionine synthase activity" . "5-methyltetrahydrofolate--homocysteine S-methyltransferase activity" . "5-methyltetrahydrofolate--homocysteine transmethylase activity" . "5-methyltetrahydrofolate-homocysteine S-methyltransferase activity" . "5-methyltetrahydrofolate:L-homocysteine S-methyltransferase activity" . "B12 N(5)-methyltetrahydrofolate homocysteine methyltransferase activity" . "B12 N5-methyltetrahydrofolate homocysteine methyltransferase activity" . "cobalamin-dependent methionine synthase activity" . "methionine synthase (cobalamin-dependent) activity" . "methyltetrahydrofolate--homocysteine vitamin B12 methyltransferase activity" . "N(5)-methyltetrahydrofolate methyltransferase activity" . "N(5)-methyltetrahydrofolate--homocysteine cobalamin methyltransferase activity" . "N(5)-methyltetrahydrofolic--homocysteine vitamin B12 transmethylase activity" . "N-methyltetrahydrofolate:L-homocysteine methyltransferase activity" . "N5-methyltetrahydrofolate methyltransferase activity" . "N5-methyltetrahydrofolate-homocysteine cobalamin methyltransferase activity" . "N5-methyltetrahydrofolic-homocysteine vitamin B12 transmethylase activity" . "tetrahydrofolate methyltransferase activity" . "tetrahydropteroylglutamate methyltransferase activity" . "tetrahydropteroylglutamic methyltransferase activity" . "vitamin B12 methyltransferase activity" . "EC:2.1.1.13" . "KEGG:R00946" . "MetaCyc:HOMOCYSMETB12-RXN" . "Reactome:REACT_108964 \"Methionine is reformed, Staphylococcus aureus N315\"" . "Reactome:REACT_109401 \"Methionine is reformed, Xenopus tropicalis\"" . "Reactome:REACT_32037 \"Methionine is reformed, Canis familiaris\"" . "Reactome:REACT_33315 \"Methionine is reformed, Rattus norvegicus\"" . "Reactome:REACT_6739 \"Methionine is reformed, Homo sapiens\"" . "Reactome:REACT_79867 \"Methionine is reformed, Escherichia coli\"" . "Reactome:REACT_82450 \"Methionine is reformed, Taeniopygia guttata\"" . "Reactome:REACT_87311 \"Methionine is reformed, Mus musculus\"" . "Reactome:REACT_88342 \"Methionine is reformed, Mycobacterium tuberculosis\"" . "Reactome:REACT_89478 \"Methionine is reformed, Gallus gallus\"" . "Reactome:REACT_91637 \"Methionine is reformed, Bos taurus\"" . "Reactome:REACT_92492 \"Methionine is reformed, Sus scrofa\"" . "Reactome:REACT_93034 \"Methionine is reformed, Caenorhabditis elegans\"" . "Reactome:REACT_97474 \"Methionine is reformed, Danio rerio\"" . "Reactome:REACT_98785 \"Methionine is reformed, Dictyostelium discoideum\"" . "RHEA:11175" . . . "MetH" .