Enzyme Nomenclature

EC 2.1

Transferring One-Carbon Groups

Sections

EC 2.1.1 Methyltransferases
EC 2.1.2 Hydroxymethyl-, Formyl- and Related Transferases
EC 2.1.3 Carboxyl- and Carbamoyltransferases
EC 2.1.4 Amidinotransferases


EC 2.1.1 Methyltransferases

('Methyltransferase' may be replaced by 'transmethylase').

Contents

See separate file for EC 2.1.1.51 to EC 2.1.1.100, EC 2.1.1.101 to EC 2.1.1.150, EC 2.1.1.151 to EC 2.1.1.200, EC 2.1.1.201 to EC 2.1.1.250, EC 2.1.1.251 to EC 2.1.1.300 and EC 2.1.1.301 to EC 2.1.1.336.

EC 2.1.1.1 nicotinamide N-methyltransferase
EC 2.1.1.2 guanidinoacetate N-methyltransferase
EC 2.1.1.3 thetin—homocysteine S-methyltransferase
EC 2.1.1.4 acetylserotonin O-methyltransferase
EC 2.1.1.5 betaine—homocysteine S-methyltransferase
EC 2.1.1.6 catechol O-methyltransferase
EC 2.1.1.7 nicotinate N-methyltransferase
EC 2.1.1.8 histamine N-methyltransferase
EC 2.1.1.9 thiol S-methyltransferase
EC 2.1.1.10 homocysteine S-methyltransferase
EC 2.1.1.11 magnesium protoporphyrin IX methyltransferase
EC 2.1.1.12 methionine S-methyltransferase
EC 2.1.1.13 methionine synthase
EC 2.1.1.14 5-methyltetrahydropteroyltriglutamate—homocysteine S-methyltransferase
EC 2.1.1.15 fatty-acid O-methyltransferase
EC 2.1.1.16 methylene-fatty-acyl-phospholipid synthase
EC 2.1.1.17 phosphatidylethanolamine N-methyltransferase
EC 2.1.1.18 polysaccharide O-methyltransferase
EC 2.1.1.19 trimethylsulfonium—tetrahydrofolate N-methyltransferase
EC 2.1.1.20 glycine N-methyltransferase
EC 2.1.1.21 methylamine—glutamate N-methyltransferase
EC 2.1.1.22 carnosine N-methyltransferase
EC 2.1.1.23 now covered by EC 2.1.1.124, EC 2.1.1.125 and EC 2.1.1.126
EC 2.1.1.24 now covered by EC 2.1.1.77, EC 2.1.1.80 and EC 2.1.1.100
EC 2.1.1.25 phenol O-methyltransferase
EC 2.1.1.26 iodophenol O-methyltransferase
EC 2.1.1.27 tyramine N-methyltransferase
EC 2.1.1.28 phenylethanolamine N-methyltransferase
EC 2.1.1.29 transferred now EC 2.1.1.202, EC 2.1.1.203 and EC 2.1.1.204
EC 2.1.1.30 deleted
EC 2.1.1.31 transferred, now EC 2.1.1.221 and EC 2.1.1.228
EC 2.1.1.32 transferred, now EC 2.1.1.213, EC 2.1.1.214, EC 2.1.1.215 and EC 2.1.1.216
EC 2.1.1.33 tRNA (guanine46-N7)-methyltransferase
EC 2.1.1.34 tRNA (guanosine18-2'-O)-methyltransferase
EC 2.1.1.35 tRNA (uracil54-C5)-methyltransferase
EC 2.1.1.36 transferred now EC 2.1.1.217, EC 2.1.1.218, EC 2.1.1.219, EC 2.1.1.220
EC 2.1.1.37 DNA (cytosine-5-)-methyltransferase
EC 2.1.1.38 O-demethylpuromycin O-methyltransferase
EC 2.1.1.39 inositol 3-methyltransferase
EC 2.1.1.40 inositol 1-methyltransferase
EC 2.1.1.41 24-sterol C-methyltransferase
EC 2.1.1.42 flavone 3'-O-methyltransferase
EC 2.1.1.43 histone-lysine N-methyltransferase
EC 2.1.1.44 L-histidine Nα-methyltransferase
EC 2.1.1.45 thymidylate synthase
EC 2.1.1.46 isoflavone 4'-O-methyltransferase
EC 2.1.1.47 indolepyruvate C-methyltransferase
EC 2.1.1.48 rRNA (adenine-N6-)-methyltransferase
EC 2.1.1.48 transferred now covered by EC 2.1.1.181, EC 2.1.1.182, EC 2.1.1.183 and EC 2.1.1.184
EC 2.1.1.49 amine N-methyltransferase
EC 2.1.1.50 loganate O-methyltransferase

See the following files for:

EC 2.1.1.51 to EC 2.1.1.100
EC 2.1.1.101 to EC 2.1.1.150
EC 2.1.1.151 to EC 2.1.1.200
EC 2.1.1.201 to EC 2.1.1.250
EC 2.1.1.251 to EC 2.1.1.300
EC 2.1.1.301 to EC 2.1.1.336

Entries

EC 2.1.1.1

Accepted name: nicotinamide N-methyltransferase

Reaction: S-adenosyl-L-methionine + nicotinamide = S-adenosyl-L-homocysteine + 1-methylnicotinamide

Other name(s): nicotinamide methyltransferase

Systematic name: S-adenosyl-L-methionine:nicotinamide N-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9029-74-7

References:

1. Cantoni, G.L. Methylation of nicotinamide with a soluble enzyme system from rat liver. J. Biol. Chem. 189 (1951) 203-216.

[EC 2.1.1.1 created 1961]

EC 2.1.1.2

Accepted name: guanidinoacetate N-methyltransferase

Reaction: S-adenosyl-L-methionine + guanidinoacetate = S-adenosyl-L-homocysteine + creatine

For diagram of reaction click here.

Other name(s): GA methylpherase; guanidinoacetate methyltransferase; guanidinoacetate transmethylase; methionine-guanidinoacetic transmethylase; guanidoacetate methyltransferase

Systematic name: S-adenosyl-L-methionine:N-guanidinoacetate methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9029-75-8

References:

1. Cantoni, G.L. and Scarano, E. The formation of S-adenosylhomocysteine in enzymatic transmethylation reactions. J. Am. Chem. Soc. 76 (1954) 4744 only.

2. Cantoni, G.L. and Vignos, P.J. Enzymatic mechanism of creatine synthesis. J. Biol. Chem. 209 (1954) 647-659.

[EC 2.1.1.2 created 1961]

EC 2.1.1.3

Accepted name: thetin—homocysteine S-methyltransferase

Reaction: dimethylsulfonioacetate + L-homocysteine = S-methylthioglycolate + L-methionine

Other name(s): dimethylthetin-homocysteine methyltransferase; thetin-homocysteine methylpherase

Systematic name: dimethylsulfonioacetate:L-homocysteine S-methyltransferase

Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, CAS registry number: 9029-76-9

References:

1. Klee, W.A., Richards, H.H. and Cantoni, G.L. The synthesis of methionine by enzymic transmethylation. VII. Existence of two separate homocysteine methylpherases on mammalian liver. Biochim. Biophys. Acta 54 (1961) 157-164.

2. Maw, G.A. Thetin-homocysteine transmethylase. A preliminary manometric study of the enzyme from rat liver. Biochem. J. 63 (1956) 116-124.

3. Maw, G.A. Thetin-homocysteine transmethylase. Some further characteristics of the enzyme from rat liver. Biochem. J. 70 (1958) 168-173.

[EC 2.1.1.3 created 1961]

EC 2.1.1.4

Accepted name: acetylserotonin O-methyltransferase

Reaction: S-adenosyl-L-methionine + N-acetylserotonin = S-adenosyl-L-homocysteine + melatonin

Glossary entries:
Melatonin: N-acetyl-5-methoxytryptamine
Serotonin: 5-hydroxytryptamine
Tryptamine: 2-(1H-indol-3-yl)ethanamine

Other name(s): hydroxyindole methyltransferase; hydroxyindole O-methyltransferase; N-acetylserotonin O-methyltransferase; acetylserotonin methyltransferase

Systematic name: S-adenosyl-L-methionine:N-acetylserotonin O-methyltransferase

Comments: Some other hydroxyindoles also act as acceptor, but more slowly.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9029-77-0

References:

1. Axelrod, J. and Weissbach, H. Purification and properties of hydroxyindole-O-methyl transferase. J. Biol. Chem. 236 (1961) 211-213.

[EC 2.1.1.4 created 1961]

EC 2.1.1.5

Accepted name: betaine—homocysteine S-methyltransferase

Reaction: trimethylammonioacetate + L-homocysteine = dimethylglycine + L-methionine

Other name(s): betaine-homocysteine methyltransferase; betaine-homocysteine transmethylase

Systematic name: trimethylammonioacetate:L-homocysteine S-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9029-78-1

References:

1. Klee, W.A., Richards, H.H. and Cantoni, G.L. The synthesis of methionine by enzymic transmethylation. VII. Existence of two separate homocysteine methylpherases on mammalian liver. Biochim. Biophys. Acta 54 (1961) 157-164.

[EC 2.1.1.5 created 1961]

EC 2.1.1.6

Accepted name: catechol O-methyltransferase

Reaction: S-adenosyl-L-methionine + a catechol = S-adenosyl-L-homocysteine + a guaiacol

Other name(s): COMT I ; COMT II; S-COMT (soluble form of catechol-O-methyltransferase); MB-COMT (membrane-bound form of catechol-O-methyltransferase); catechol methyltransferase; catecholamine O-methyltransferase

Systematic name: S-adenosyl-L-methionine:catechol O-methyltransferase

Comments: The mammalian enzyme acts more rapidly on catecholamines such as adrenaline or noradrenaline than on catechols.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9012-25-3

References:

1. Axelrod, J. and Tomchick, R. Enzymatic O-methylation of epinephrine and other catechols. J. Biol. Chem. 233 (1958) 702-705.

2. Gulliver, P.A. and Tipton, K.F. The purification and properties of pig brain catechol-O-methyltransferase. J. Neurochem. 32 (1979) 1525-1529. [PMID: 438821]

3. Huh, M.M.O. and Friedhof, A.J. Multiple molecular forms of catechol-O-methyltransferase. Evidence for two distinct forms, and their purification and physical characterization. J. Biol. Chem. 254 (1979) 299-308. [PMID: 762061]

[EC 2.1.1.6 created 1965]

EC 2.1.1.7

Accepted name: nicotinate N-methyltransferase

Reaction: S-adenosyl-L-methionine + nicotinate = S-adenosyl-L-homocysteine + N-methylnicotinate

Other name(s): furanocoumarin 8-methyltransferase; furanocoumarin 8-O-methyltransferase

Systematic name: S-adenosyl-L-methionine:nicotinate N-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 9029-79-2

References:

1. Joshi, J.G. and Handler, P. Biosynthesis of trigonelline. J. Biol. Chem. 235 (1960) 2981-2983.

[EC 2.1.1.7 created 1965]

EC 2.1.1.8

Accepted name: histamine N-methyltransferase

Reaction: S-adenosyl-L-methionine + histamine = S-adenosyl-L-homocysteine + Nτ-methylhistamine

Other name(s): histamine 1-methyltransferase; histamine methyltransferase; histamine-methylating enzyme; imidazolemethyltransferase; S-adenosylmethionine-histamine N-methyltransferase

Systematic name: S-adenosyl-L-methionine:histamine N-tele-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9029-80-5

References:

1. Brown, D.D., Tomchick, R. and Axelrod, J. The distribution and properties of a histamine-methylating enzyme. J. Biol. Chem. 234 (1959) 2948-2950.

[EC 2.1.1.8 created 1965]

EC 2.1.1.9

Accepted name: thiol S-methyltransferase

Reaction: S-adenosyl-L-methionine + a thiol = S-adenosyl-L-homocysteine + a methyl thioether

Other name(s): S-methyltransferase; thiol methyltransferase; TMT

Systematic name: S-adenosyl-L-methionine:thiol S-methyltransferase

Comments: H2S and a variety of alkyl, aryl and heterocyclic thiols and hydroxy thiols can act as acceptors.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, UM-BBD, CAS registry number: 9029-81-6

References:

1. Borchardt, R.T. and Cheng, C.F. Purification and characterization of rat liver microsomal thiol methyltransferase. Biochim. Biophys. Acta 522 (1978) 340-353. [PMID: 623768]

2. Bremer, J. and Greenberg, D.M. Enzymic methylation of foreign sulfhydryl compounds Biochim. Biophys. Acta 46 (1961) 217-224.

3. Weisiger, R.A. and Jakoby, W.B. Thiol S-methyltransferase from rat liver. Arch. Biochem. Biophys. 196 (1979) 631-637. [PMID: 485170]

[EC 2.1.1.9 created 1965]

EC 2.1.1.10

Accepted name: homocysteine S-methyltransferase

Reaction: S-methyl-L-methionine + L-homocysteine = 2 L-methionine

Other name(s): S-adenosylmethionine homocysteine transmethylase; S-methylmethionine homocysteine transmethylase; adenosylmethionine transmethylase; methylmethionine:homocysteine methyltransferase; adenosylmethionine:homocysteine methyltransferase; homocysteine methylase; homocysteine methyltransferase; homocysteine transmethylase; L-homocysteine S-methyltransferase; S-adenosyl-L-methionine:L-homocysteine methyltransferase; S-adenosylmethionine-homocysteine transmethylase; S-adenosylmethionine:homocysteine methyltransferase

Systematic name: S-methyl-L-methionine:L-homocysteine S-methyltransferase

Comments: The enzyme uses S-adenosyl-L-methionine as methyl donor less actively than S-methyl-L-methionine.

Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, CAS registry number: 9012-40-2

References:

1. Balish, E. and Shapiro, S.K. Methionine biosynthesis in Escherichia coli: induction and repression of methylmethionine (or adenosylmethionine):homocysteine methyltransferase. Arch. Biochem. Biophys. 119 (1967) 62-68. [PMID: 4861151]

2. Shapiro, S.K. Adenosylmethionine-homocysteine transmethylase. Biochim. Biophys. Acta 29 (1958) 405-409. [PMID: 13572358]

3. Shapiro, S.K. and Yphantis, D.A. Assay of S-methylmethionine and S-adenosylmethionine homocysteine transmethylases. Biochim. Biophys. Acta 36 (1959) 241-244. [PMID: 14445542]

4. Mudd, S.H. and Datko, A.H. The S-Methylmethionine Cycle in Lemna paucicostata. Plant Physiol. 93 (1990) 623-630. [PMID: 16667513]

5. Ranocha, P., McNeil, S.D., Ziemak, M.J., Li, C., Tarczynski, M.C. and Hanson, A.D. The S-methylmethionine cycle in angiosperms: ubiquity, antiquity and activity. Plant J. 25 (2001) 575-584. [PMID: 11309147]

6. Ranocha, P., Bourgis, F., Ziemak, M.J., Rhodes, D., Gage, D.A. and Hanson, A.D. Characterization and functional expression of cDNAs encoding methionine-sensitive and -insensitive homocysteine S-methyltransferases from Arabidopsis. J. Biol. Chem. 275 (2000) 15962-15968. [PMID: 10747987]

7. Grue-Sorensen, G., Kelstrup, E., Kjaer, A. and Madsen, J.O.: Diastereospecific, enzymically catalysed transmethylation from S-methylL-L-methionine to L-homocysteine, a naturally occurring process. J. Chem. Soc. Perkin Trans. 1 (1984) 1091-1097.

[EC 2.1.1.10 created 1965, modified 2010]

EC 2.1.1.11

Accepted name: magnesium protoporphyrin IX methyltransferase

Reaction: S-adenosyl-L-methionine + magnesium protoporphyrin IX = S-adenosyl-L-homocysteine + magnesium protoporphyrin IX 13-methyl ester

For diagram of reaction click here (chlorophyll biosynthesis).

Other name(s): Mg-protoporphyrin IX methyltransferase; S-adenosylmethionine-magnesium protoporphyrin methyltransferase; magnesium-protoporphyrin O-methyltransferase; (–)-S-adenosyl-L-methionine:magnesium-protoporphyrin IX methyltransferase; S-adenosyl-L-methionine:Mg protoporphyrin methyltransferase; S-adenosylmethioninemagnesium protoporphyrin methyltransferase; S-adenosyl-L-methionine:magnesium-protoporphyrin O-methyltransferase

Systematic name: S-adenosyl-L-methionine:magnesium-protoporphyrin-IX O-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 9029-82-7

References:

1. Gibson, K.D., Neuberger, A. and Tait, G.H. Studies on the biosynthesis of porphyrin and bacteriochlorophyll by Rhodopseudomonas spheroides. 4. S-Adenosylmethioninemagnesium protoporphyrin methyltransferase. Biochem. J. 88 (1963) 325-334.

2. Shepherd, M., Reid, J.D. and Hunter, C.N. Purification and kinetic characterisation of the magnesium protoporphyrin IX methyltransferase from Synechocystis PCC6803. Biochem. J. 371 (2003) 351-360. [PMID: 12489983]

3. Bollivar, D.W., Jiang, Z.Y., Bauer, C.E. and Beale, S.I. Heterologous expression of the bchM gene product from Rhodobacter capsulatus and demonstration that it encodes S-adenosyl-L-methionine:Mg-protoporphyrin IX methyltransferase. J. Bacteriol. 176 (1994) 5290-5296. [PMID: 8071204]

4. Gibson, L.C. and Hunter, C.N. The bacteriochlorophyll biosynthesis gene, bchM, of Rhodobacter sphaeroides encodes S-adenosyl-L-methionine: Mg protoporphyrin IX methyltransferase. FEBS Lett. 352 (1994) 127-130. [PMID: 7925960]

5. Ebbon, J.G. and Tait, G.H. Studies on S-adenosylmethionine-magnesium protoporphyrin methyltransferase in Euglena gracilis strain Z. Biochem. J. 111 (1969) 573-582. [PMID: 5774480]

[EC 2.1.1.11 created 1965, modified 2003]

EC 2.1.1.12

Accepted name: methionine S-methyltransferase

Reaction: S-adenosyl-L-methionine + L-methionine = S-adenosyl-L-homocysteine + S-methyl-L-methionine

Other name(s): S-adenosyl methionine:methionine methyl transferase; methionine methyltransferase; S-adenosylmethionine transmethylase; S-adenosylmethionine-methionine methyltransferase

Systematic name: S-adenosyl-L-methionine:L-methionine S-methyltransferase

Comments: Requires Zn2+ or Mn2+

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 9027-77-4

References:

1. Karr, D. Tweto, J. and Albersheim, P. S-Adenosyl methionine: methionine methyl transferase from wheat germ. Arch. Biochem. Biophys. 121 (1967) 732-738. [PMID: 6078098]

[EC 2.1.1.12 created 1972]

EC 2.1.1.13

Accepted name: methionine synthase

Reaction: 5-methyltetrahydrofolate + L-homocysteine = tetrahydrofolate + L-methionine

For diagram of reaction click here and mechanism click here.

Other name(s): 5-methyltetrahydrofolate—homocysteine S-methyltransferase; 5-methyltetrahydrofolate—homocysteine transmethylase; N-methyltetrahydrofolate:L-homocysteine methyltransferase; N5-methyltetrahydrofolate methyltransferase; N5-methyltetrahydrofolate—homocysteine cobalamin methyltransferase; N5-methyltetrahydrofolic—homocysteine vitamin B12 transmethylase; B12 N5-methyltetrahydrofolate homocysteine methyltransferase; methyltetrahydrofolate—homocysteine vitamin B12 methyltransferase; tetrahydrofolate methyltransferase; tetrahydropteroylglutamate methyltransferase; tetrahydropteroylglutamic methyltransferase; vitamin B12 methyltransferase; cobalamin-dependent methionine synthase; methionine synthase (cobalamin-dependent); MetH

Systematic name: 5-methyltetrahydrofolate:L-homocysteine S-methyltransferase

Comments: Contains zinc and cobamide. The enzyme becomes inactivated occasionally during its cycle by oxidation of Co(I) to Co(II). Reactivation by reductive methylation is catalysed by the enzyme itself, with S-adenosyl-L-methionine as the methyl donor and a reducing system. For the mammalian enzyme, the reducing system involves NADPH and EC 1.16.1.8, [methionine synthase] reductase. In bacteria, the reducing agent is flavodoxin, and no further catalyst is needed (the flavodoxin is kept in the reduced state by NADPH and EC 1.18.1.2, ferredoxin—NADP+ reductase). Acts on the monoglutamate as well as the triglutamate folate, in contrast with EC 2.1.1.14, 5-methyltetrahydropteroyltriglutamate—homocysteine S-methyltransferase, which acts only on the triglutamate.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9033-23-2

References:

1. Burton, E.G. and Sakami, W. The formation of methionine from the monoglutamate form of methyltetrahydrofolate by higher plants. Biochem. Biophys. Res. Commun. 36 (1969) 228-234. [PMID: 5799642]

2. Foster, M.A., Dilworth, M.J. and Woods, D.D. Cobalamin and the synthesis of methionine by Escherichia coli. Nature 201 (1964) 39-42.

3. Guest, J.R., Friedman, S., Foster, M.A., Tejerina, G. and Woods, D.D. Transfer of the methyl group from N5-methyltetrahydrofolates to homocysteine in Escherichia coli. Biochem. J. 92 (1964) 497-504.

4. Loughlin, R.E., Elford, H.L. and Buchanan, J.M. Enzymatic synthesis of the methyl group of methionine. VII. Isolation of a cobalamin-containing transmethylase (5-methyltetrahydro-folate-homocysteine) from mammalian liver. J. Biol. Chem. 239 (1964) 2888-2895.

5. Taylor, R.T. Escherichia coli B N5-methyltetrahydrofolate-homocysteine cobalamin methyltransferase: gel-filtration behavior of apoenzyme and holoenzymes. Biochim. Biophys. Acta 242 (1971) 355-364. [PMID: 4946148]

6. Jarrett, J.T., Huang, S. and Matthews, R.G. Methionine synthase exists in two distinct conformations that differ in reactivity toward methyltetrahydrofolate, adenosylmethionine, and flavodoxin. Biochemistry 37 (1998) 5372-5382. [PMID: 9548919]

7. Peariso, K., Goulding, C.W., Huang, S., Matthews, R.G. and Penner-Hahn, J.E. Characterization of the zinc binding site in methionine synthase enzymes of Escherichia coli: The role of zinc in the methylation of homocysteine. J. Am. Chem. Soc. 120 (1998) 8410-8416.

8. Hall, D.A., Jordan-Starck, T.C., Loo, R.O., Ludwig, M.L. and Matthews, R.G. Interaction of flavodoxin with cobalamin-dependent methionine synthase. Biochemistry 39 (2000) 10711-10719. [PMID: 10978155]

9. Bandarian, V., Pattridge, K.A., Lennon, B.W., Huddler, D.P., Matthews, R.G. and Ludwig, M.L. Domain alternation switches B12-dependent methionine synthase to the activation conformation. Nat. Struct. Biol. 9 (2002) 53-56. [PMID: 11731805]

[EC 2.1.1.13 created 1972, modified 2003]

EC 2.1.1.14

Accepted name: 5-methyltetrahydropteroyltriglutamate—homocysteine S-methyltransferase

Reaction: 5-methyltetrahydropteroyltri-L-glutamate + L-homocysteine = tetrahydropteroyltri-L-glutamate + L-methionine

For diagram of reaction click here.

Other name(s): tetrahydropteroyltriglutamate methyltransferase; homocysteine methylase; methyltransferase, tetrahydropteroylglutamate-homocysteine transmethylase; methyltetrahydropteroylpolyglutamate:homocysteine methyltransferase; cobalamin-independent methionine synthase; methionine synthase (cobalamin-independent); MetE

Systematic name: 5-methyltetrahydropteroyltri-L-glutamate:L-homocysteine S-methyltransferase

Comments: Requires phosphate and contains zinc. The enzyme from Escherichia coli also requires a reducing system. Unlike EC 2.1.1.13, methionine synthase, this enzyme does not contain cobalamin.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9068-29-5

References:

1. Guest, J.R., Friedman, S., Foster, M.A., Tejerina, G. and Woods, D.D. Transfer of the methy grouup from N5-methyltetrahydrofolates to homocysteine in Escherichia coli. Biochem. J. 92 (1964) 497-504.

2. Whitfield, C.D., Steers, E.J., Jr. and Weissbach, H. Purification and properties of 5-methyltetrahydropteroyltriglutamate-homocysteine transmethylase. J. Biol. Chem. 245 (1970) 390-401. [PMID: 4904482]

3. Eichel, J., Gonzalez, J.C., Hotze, M., Matthews, R.G. and Schroder, J. Vitamin B12-independent methionine synthase from a higher-plant (Catharanthus roseus) - molecular characterization, regulation, heterologous expression, and enzyme properties. Eur. J. Biochem. 230 (1995) 1053-1058. [PMID: 7601135]

4. Gonzalez, J.C., Peariso, K., PennerHahn, J.E. and Matthews, R.G. Cobalamin-independent methionine synthase from Escherichia coli: A zinc metalloenzyme. Biochemistry 35 (1996) 12228-12234. [PMID: 8823155]

5. Peariso, K., Goulding, C.W., Huang, S., Matthews, R.G. and Penner-Hahn, J.E. Characterization of the zinc binding site in methionine synthase enzymes of Escherichia coli: The role of zinc in the methylation of homocysteine. J. Am. Chem. Soc. 120 (1998) 8410-8416.

[EC 2.1.1.14 created 1972, modified 2003]

EC 2.1.1.15

Accepted name: fatty-acid O-methyltransferase

Reaction: S-adenosyl-L-methionine + a fatty acid = S-adenosyl-L-homocysteine + a fatty acid methyl ester

Other name(s): fatty acid methyltransferase; fatty acid O-methyltransferase

Systematic name: S-adenosyl-L-methionine:fatty-acid O-methyltransferase

Comments: Oleic acid is the most effective fatty acid acceptor.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37256-89-6

References:

1. Akamatsu, Y. and Law, J.H. The enzymatic synthesis of fatty acid methyl esters by carboxyl group alkylation. J. Biol. Chem. 245 (1970) 709-713. [PMID: 4984625]

[EC 2.1.1.15 created 1972]

EC 2.1.1.16

Accepted name: methylene-fatty-acyl-phospholipid synthase

Reaction: S-adenosyl-L-methionine + phospholipid olefinic fatty acid = S-adenosyl-L-homocysteine + phospholipid methylene fatty acid

Other name(s): unsaturated-phospholipid methyltransferase

Systematic name: S-adenosyl-L-methionine:unsaturated-phospholipid methyltransferase (methenylating)

Comments: The enzyme transfers a methyl group to the 10-position of a δ-olefinic acyl chain in phosphatidylglycerol or phosphatidylinositol or, more slowly, phosphatidylethanolamine; subsequent proton transfer produces a 10-methylene group (cf. EC 2.1.1.79 cyclopropane-fatty-acyl-phospholipid synthase).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37256-90-9

References:

1. Akamatsu, Y. and Law, J.H. Enzymatic alkylenation of phospholipid fatty acid chains by extracts of Mycobacterium phlei. J. Biol. Chem. 245 (1970) 701-708. [PMID: 4313604]

[EC 2.1.1.16 created 1972, modified 1986]

EC 2.1.1.17

Accepted name: phosphatidylethanolamine N-methyltransferase

Reaction: S-adenosyl-L-methionine + phosphatidylethanolamine = S-adenosyl-L-homocysteine + phosphatidyl-N-methylethanolamine

Other name(s): PEMT; LMTase; lipid methyl transferase; phosphatidylethanolamine methyltransferase; phosphatidylethanolamine-N-methylase; phosphatidylethanolamine-S-adenosylmethionine methyltransferase

Systematic name: S-adenosyl-L-methionine:phosphatidylethanolamine N-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37256-91-0

References:

1. Hirata, F., Viveros, O.H., Diliberto, E.J., Jr. and Axelrod, J. Identification and properties of two methyltransferases in conversion of phosphatidylethanolamine to phosphatidylcholine. Proc. Natl. Acad. Sci. USA 75 (1978) 1718-1721. [PMID: 25437]

2. Morgan, T.E. Isolation and characterization of lipid N-methyltransferase from dog lung. Biochim. Biophys. Acta 178 (1969) 21-34. [PMID: 5773456]

3. Schneider, W.J. and Vance, D.E. Conversion of phosphatidylethanolamine to phosphatidylcholine in rat liver. Partial purification and characterization of the enzymatic activities. J. Biol. Chem. 254 (1979) 3886-3891. [PMID: 438165]

[EC 2.1.1.17 created 1972]

EC 2.1.1.18

Accepted name: polysaccharide O-methyltransferase

Reaction: S-adenosyl-L-methionine + (1→4)-α-D-glucooligosaccharide = S-adenosyl-L-homocysteine + oligosaccharide containing 6-methyl-D-glucose units

Other name(s): polysaccharide methyltransferase; acylpolysacharide 6-methyltransferase; S-adenosyl-L-methionine:1,4-α-D-glucan 6-O-methyltransferase

Systematic name: S-adenosyl-L-methionine:(1→4)-α-D-glucan 6-O-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37205-56-4

References:

1. Ferguson, J.A. and Ballou, C.E. Biosynthesis of a mycobacterial lipopolysaccharide. Properties of the polysaccharide methyltransferase. J. Biol. Chem. 245 (1970) 4213-4223. [PMID: 5503262]

[EC 2.1.1.18 created 1972]

EC 2.1.1.19

Accepted name: trimethylsulfonium—tetrahydrofolate N-methyltransferase

Reaction: trimethylsulfonium + tetrahydrofolate = dimethylsulfide + 5-methyltetrahydrofolate

For diagram of reaction click here or click here.

Other name(s): trimethylsulfonium-tetrahydrofolate methyltransferase

Systematic name: trimethylsulfonium:tetrahydrofolate N-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37256-92-1

References:

1. Wagner, C., Lusty, S.M., Jr., Kung, H.-F. and Rodgers, N.L. Preparation and properties of trimethylsulfonium-tetrahydrofolate methyltransferase. J. Biol. Chem. 242 (1967) 1287-1293. [PMID: 6023571]

[EC 2.1.1.19 created 1972]

EC 2.1.1.20

Accepted name: glycine N-methyltransferase

Reaction: S-adenosyl-L-methionine + glycine = S-adenosyl-L-homocysteine + sarcosine

Glossary: sarcosine = N-methylglycine

Other name(s): glycine methyltransferase; S-adenosyl-L-methionine:glycine methyltransferase; GNMT

Systematic name: S-adenosyl-L-methionine:glycine N-methyltransferase

Comments: This enzyme is thought to play an important role in the regulation of methyl group metabolism in the liver and pancreas by regulating the ratio between S-adenosyl-L-methionine and S-adenosyl-L-homocysteine. It is inhibited by 5-methyltetrahydrofolate pentaglutamate [4]. Sarcosine, which has no physiological role, is converted back into glycine by the action of EC 1.5.8.3, sarcosine dehydrogenase.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37228-72-1

References:

1. Blumenstein, J. and Williams, G.R. Glycine methyltransferase. Can. J. Biochem. Physiol. 41 (1963) 201-210. [PMID: 13971907]

2. Ogawa, H., Gomi, T., Takusagawa, F. and Fujioka, M. Structure, function and physiological role of glycine N-methyltransferase. Int. J. Biochem. Cell Biol. 30 (1998) 13-26. [PMID: 9597750]

3. Yeo, E.J., Briggs, W.T. and Wagner, C. Inhibition of glycine N-methyltransferase by 5-methyltetrahydrofolate pentaglutamate. J. Biol. Chem. 274 (1999) 37559-37564. [PMID: 10608809]

4. Martinov, M.V., Vitvitsky, V.M., Mosharov, E.V., Banerjee, R. and Ataullakhanov, F.I. A substrate switch: a new mode of regulation in the methionine metabolic pathway. J. Theor. Biol. 204 (2000) 521-532. [PMID: 10833353]

5. Takata, Y., Huang, Y., Komoto, J., Yamada, T., Konishi, K., Ogawa, H., Gomi, T., Fujioka, M. and Takusagawa, F. Catalytic mechanism of glycine N-methyltransferase. Biochemistry 42 (2003) 8394-8402. [PMID: 12859184]

6. Pakhomova, S., Luka, Z., Grohmann, S., Wagner, C. and Newcomer, M.E. Glycine N-methyltransferases: a comparison of the crystal structures and kinetic properties of recombinant human, mouse and rat enzymes. Proteins 57 (2004) 331-337. [PMID: 15340920]

[EC 2.1.1.20 created 1972, modified 2005]

EC 2.1.1.21

Accepted name: methylamine—glutamate N-methyltransferase

Reaction: methylamine + L-glutamate = NH3 + N-methyl-L-glutamate

Other name(s): N-methylglutamate synthase; methylamine-glutamate methyltransferase

Systematic name: methylamine:L-glutamate N-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 9045-32-3

References:

1. Shaw, W.V., Tsai, L. and Stadtman, E.R. The enzymatic synthesis of N-methylglutamic acid. J. Biol. Chem. 241 (1966) 935-945. [PMID: 5905132]

[EC 2.1.1.21 created 1972]

EC 2.1.1.22

Accepted name: carnosine N-methyltransferase

Reaction: S-adenosyl-L-methionine + carnosine = S-adenosyl-L-homocysteine + anserine

Systematic name: S-adenosyl-L-methionine:carnosine N-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37256-93-2

References:

1. McManus, I.R. Enzymatic synthesis of anserine in skeletal muscle by N-methylation of carnosine. J. Biol. Chem. 237 (1962) 1207-1211.

[EC 2.1.1.22 created 1972]

[EC 2.1.1.23 Deleted entry: protein-arginine N-methyltransferase. Now listed as EC 2.1.1.124 [cytochrome c]-arginine N-methyltransferase, EC 2.1.1.125 histone-arginine N-methyltransferase and EC 2.1.1.126 [myelin basic protein]-arginine N-methyltransferase. (EC 2.1.1.23 created 1972, modified 1976, modified 1983, deleted 1999)]

[EC 2.1.1.24 Deleted entry: protein-γ-glutamate O-methyltransferase. Now listed as EC 2.1.1.77 protein-L-isoaspartate(D-aspartate) O-methyltransferase, EC 2.1.1.80 protein-glutamate O-methyltransferase and EC 2.1.1.100 protein-S-isoprenylcysteine O-methyltransferase. (EC 2.1.1.24 created 1972, modified 1983, modified 1989, deleted 1992)]

EC 2.1.1.25

Accepted name: phenol O-methyltransferase

Reaction: S-adenosyl-L-methionine + phenol = S-adenosyl-L-homocysteine + anisole

Other name(s): PMT

Systematic name: S-adenosyl-L-methionine:phenol O-methyltransferase

Comments: Acts on a wide variety of simple alkyl-, methoxy- and halo-phenols.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37256-94-3

References:

1. Axelrod, J. and Daly, J. Phenol-O-methyltransferase. Biochim. Biophys. Acta 159 (1968) 472-478. [PMID: 5657870]

[EC 2.1.1.25 created 1972]

EC 2.1.1.26

Accepted name: iodophenol O-methyltransferase

Reaction: S-adenosyl-L-methionine + 2-iodophenol = S-adenosyl-L-homocysteine + 2-iodophenol methyl ether

Systematic name: S-adenosyl-L-methionine:2-iodophenol O-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37256-95-4

References:

1. Tomita, K., Cha, C.-J. and Lardy, H.A. Enzymic O-methylation of iodinated phenols and thyroid hormones. J. Biol. Chem. 239 (1964) 1202-1207.

[EC 2.1.1.26 created 1972]

EC 2.1.1.27

Accepted name: tyramine N-methyltransferase

Reaction: S-adenosyl-L-methionine + tyramine = S-adenosyl-L-homocysteine + N-methyltyramine

Other name(s): DIB O-methyltransferase (3,5-diiodo-4-hydroxy-benzoic acid); S-adenosyl-methionine:tyramine N-methyltransferase; tyramine methylpherase

Systematic name: S-adenosyl-L-methionine:tyramine N-methyltransferase

Comments: Has some activity on phenylethylamine analogues.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37256-96-5

References:

1. Mann, J.D. and Mudd, S.H. Alkaloids and plant metabolism. IV. The tyramine methylpherase of barley roots. J. Biol. Chem. 238 (1963) 381-385.

[EC 2.1.1.27 created 1972]

EC 2.1.1.28

Accepted name: phenylethanolamine N-methyltransferase

Reaction: S-adenosyl-L-methionine + phenylethanolamine = S-adenosyl-L-homocysteine + N-methylphenylethanolamine

For diagram click here.

Other name(s): noradrenaline N-methyltransferase; noradrenalin N-methyltransferase; norepinephrine methyltransferase; norepinephrine N-methyltransferase; phenethanolamine methyltransferase; phenethanolamine N-methyltransferase

Systematic name: S-adenosyl-L-methionine:phenylethanolamine N-methyltransferase

Comments: Acts on various phenylethanolamines; converts noradrenaline into adrenaline.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9037-68-7

References:

1. Axelrod, J. Purification and properties of phenylethanolamine-N-methyl transferase. J. Biol. Chem. 237 (1962) 1657-1660.

2. Connett, R.J. and Kirschner, N. Purification and properties of bovine phenylethanolamine N-methyltransferase. J. Biol. Chem. 245 (1970) 329-334. [PMID: 5412063]

[EC 2.1.1.28 created 1972]

[EC 2.1.1.29 Transferred entry: tRNA (cytosine-5-)-methyltransferase. Now covered by EC 2.1.1.202 [multisite-specific tRNA:(cytosine-C5)-methyltransferase], EC 2.1.1.203 [tRNA (cytosine34-C5)-methyltransferase] and EC 2.1.1.204 [RNA (cytosine38-C5)-methyltransferase]. (EC 2.1.1.29 created 1972, deleted 2011)]

[EC 2.1.1.30 Deleted entry: tRNA (purine-2- or -6-)-methyltransferase. Reactions previously described are due to EC 2.1.1.32 tRNA (guanine-N2-)-methyltransferase. (EC 2.1.1.30 created 1972, deleted 1981)]

[EC 2.1.1.31 Transferred entry: tRNA (guanine-N1-)-methyltransferase. Now covered by EC 2.1.1.221 (tRNA (guanine9-N1)-methyltransferase) and EC 2.1.1.228 (tRNA (guanine37-N1)-methyltransferase). (EC 2.1.1.31 created 1972, deleted 2011)]

[EC 2.1.1.32 Transferred entry: tRNA (guanine-N2-)-methyltransferase. Now covered by by EC 2.1.1.213 [tRNA (guanine10-N2)-dimethyltransferase], EC 2.1.1.214 [tRNA (guanine10-N2)-monomethyltransferase], EC 2.1.1.215 [tRNA (guanine26-N2/guanine27-N2)-dimethyltransferase] and EC 2.1.1.216 [tRNA (guanine26-N2)-dimethyltransferase] (EC 2.1.1.32 created 1972, deleted 2011)]

EC 2.1.1.33

Accepted name: tRNA (guanine46-N7)-methyltransferase

Reaction: S-adenosyl-L-methionine + guanine46 in tRNA = S-adenosyl-L-homocysteine + N7-methylguanine46 in tRNA

Other name(s): Trm8/Trm82; TrmB; tRNA (m7G46) methyltransferase; transfer ribonucleate guanine 7-methyltransferase; 7-methylguanine transfer ribonucleate methylase; tRNA guanine 7-methyltransferase; N7-methylguanine methylase; S-adenosyl-L-methionine:tRNA (guanine-7-N-)-methyltransferase

Systematic name: S-adenosyl-L-methionine:tRNA (guanine-N7)-methyltransferase

Comments: The enzyme specifically methylates guanine46 at N7 in tRNA.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37257-00-4

References:

1. Aschhoff, H.J., Elten, H., Arnold, H.H., Mahal, G., Kersten, W. and Kersten, H. 7-Methylguanine specific tRNA-methyltransferase from Escherichia coli. Nucleic Acids Res. 3 (1976) 3109-3122. [PMID: 794833]

2. Zegers, I., Gigot, D., van Vliet, F., Tricot, C., Aymerich, S., Bujnicki, J.M., Kosinski, J. and Droogmans, L. Crystal structure of Bacillus subtilis TrmB, the tRNA (m7G46) methyltransferase. Nucleic Acids Res. 34 (2006) 1925-1934. [PMID: 16600901]

3. Purta, E., van Vliet, F., Tricot, C., De Bie, L.G., Feder, M., Skowronek, K., Droogmans, L. and Bujnicki, J.M. Sequence-structure-function relationships of a tRNA (m7G46) methyltransferase studied by homology modeling and site-directed mutagenesis. Proteins 59 (2005) 482-488. [PMID: 15789416]

4. Liu, Q., Gao, Y., Yang, W., Zhou, H., Gao, Y., Zhang, X., Teng, M. and Niu, L. Crystallization and preliminary crystallographic analysis of tRNA (m7G46) methyltransferase from Escherichia coli. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 64 (2008) 743-745. [PMID: 18678947]

5. Alexandrov, A., Martzen, M.R. and Phizicky, E.M. Two proteins that form a complex are required for 7-methylguanosine modification of yeast tRNA. RNA 8 (2002) 1253-1266. [PMID: 12403464]

[EC 2.1.1.33 created 1972, modified 2011]

EC 2.1.1.34

Accepted name: tRNA (guanosine18-2'-O)-methyltransferase

Reaction: S-adenosyl-L-methionine + guanosine18 in tRNA = S-adenosyl-L-homocysteine + 2'-O-methylguanosine18 in tRNA

Other name(s): tRNA (Gm18) 2'-O-methyltransferase; tRNA (Gm18) methyltransferase; TrmH; SpoU

Systematic name: S-adenosyl-L-methionine:tRNA (guanosine18-2'-O)-methyltransferase

Comments: The enzyme catalyses the methylation of guanosine18 in tRNA.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37257-01-5

References:

1. Gefter, M.L. The in vitro synthesis of 2'-O-methylguanosine and 2-methylthio 6N (γ,γ-dimethylallyl) adenosine in transfer RNA of Escherichia coli. Biochem. Biophys. Res. Commun. 36 (1969) 435-441. [PMID: 4898378]

2. Kumagai, I., Watanabe, K. and Oshima, T. Thermally induced biosynthesis of 2'-O-methylguanosine in tRNA from an extreme thermophile, Thermus thermophilus HB27. Proc. Natl. Acad. Sci. USA 77 (1980) 1922-1926. [PMID: 6990416]

3. Hori, H., Yamazaki, N., Matsumoto, T., Watanabe, Y., Ueda, T., Nishikawa, K., Kumagai, I. and Watanabe, K. Substrate recognition of tRNA (guanosine-2'-)-methyltransferase from Thermus thermophilus HB27. J. Biol. Chem. 273 (1998) 25721-25727. [PMID: 9748240]

4. Pleshe, E., Truesdell, J. and Batey, R.T. Structure of a class II TrmH tRNA-modifying enzyme from Aquifex aeolicus. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 61 (2005) 722-728. [PMID: 16511140]

5. Ochi, A., Makabe, K., Kuwajima, K. and Hori, H. Flexible recognition of the tRNA G18 methylation target site by TrmH methyltransferase through first binding and induced fit processes. J. Biol. Chem. 285 (2010) 9018-9029. [PMID: 20053984]

[EC 2.1.1.34 created 1972, modified 2005, modified 2011]

EC 2.1.1.35

Accepted name: tRNA (uracil54-C5)-methyltransferase

Reaction: S-adenosyl-L-methionine + uracil54 in tRNA = S-adenosyl-L-homocysteine + 5-methyluracil54 in tRNA

Other name(s): transfer RNA uracil54 5-methyltransferase; transfer RNA uracil54 methylase; tRNA uracil54 5-methyltransferase; m5U54-methyltransferase; tRNA:m5U54-methyltransferase; RUMT; TrmA; 5-methyluridine54 tRNA methyltransferase; tRNA(uracil-54,C5)-methyltransferase; Trm2; tRNA(m5U54)methyltransferase

Systematic name: S-adenosyl-L-methionine:tRNA (uracil54-C5)-methyltransferase

Comments: Unlike this enzyme, EC 2.1.1.74 (methylenetetrahydrofolate—tRNA-(uracil54-C5)-methyltransferase (FADH2-oxidizing)), uses 5,10-methylenetetrahydrofolate and FADH2 to supply the atoms for methylation of U54 [4].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 37257-02-6

References:

1. Björk, G.R. and Svensson, I. Studies on microbial RNA. Fractionation of tRNA methylases from Saccharomyces cerevisiae. Eur. J. Biochem. 9 (1969) 207-215. [PMID: 4896260]

2. Greenberg, R. and Dudock, B. Isolation and characterization of m5U-methyltransferase from Escherichia coli. J. Biol. Chem. 255 (1980) 8296-8302. [PMID: 6997293]

3. Hurwitz, J., Gold, M. and Anders, M. The enzymatic methylation of ribonucleic acid and deoxyribonucleic acid. 3. Purification of soluble ribonucleic acid-methylating enzymes. J. Biol. Chem. 239 (1964) 3462-3473. [PMID: 14245404]

4. Delk, A.S., Nagle, D.P., Jr. and Rabinowitz, J.C. Methylenetetrahydrofolate-dependent biosynthesis of ribothymidine in transfer RNA of Streptococcus faecalis. Evidence for reduction of the 1-carbon unit by FADH2. J. Biol. Chem. 255 (1980) 4387-4390. [PMID: 6768721]

5. Kealey, J.T., Gu, X. and Santi, D.V. Enzymatic mechanism of tRNA (m5U54)methyltransferase. Biochimie 76 (1994) 1133-1142. [PMID: 7748948]

6. Gu, X., Ivanetich, K.M. and Santi, D.V. Recognition of the T-arm of tRNA by tRNA (m5U54)-methyltransferase is not sequence specific. Biochemistry 35 (1996) 11652-11659. [PMID: 8794745]

7. Becker, H.F., Motorin, Y., Sissler, M., Florentz, C. and Grosjean, H. Major identity determinants for enzymatic formation of ribothymidine and pseudouridine in the TΨ-loop of yeast tRNAs. J. Mol. Biol. 274 (1997) 505-518. [PMID: 9417931]

8. Walbott, H., Leulliot, N., Grosjean, H. and Golinelli-Pimpaneau, B. The crystal structure of Pyrococcus abyssi tRNA (uracil-54, C5)-methyltransferase provides insights into its tRNA specificity. Nucleic Acids Res. 36 (2008) 4929-4940. [PMID: 18653523]

[EC 2.1.1.35 created 1972, modified 2011]

[EC 2.1.1.36 Transferred entry: tRNA (adenine-N1-)-methyltransferase. Now covered by EC 2.1.1.217 (tRNA (adenine22-N1)-methyltransferase), EC 2.1.1.218 (tRNA (adenine9-N1)-methyltransferase), EC 2.1.1.219 (tRNA (adenine57-N1/adenine58-N1)-methyltransferase), EC 2.1.1.220 (tRNA (adenine58-N1)-methyltransferase). (EC 2.1.1.36 created 1972, deleted 2011)]

EC 2.1.1.37

Accepted name: DNA (cytosine-5-)-methyltransferase

Reaction: S-adenosyl-L-methionine + DNA containing cytosine = S-adenosyl-L-homocysteine + DNA containing 5-methylcytosine

Other name(s): EcoRI methylase; DNA 5-cytosine methylase; DNA cytosine C5 methylase; DNA cytosine methylase; DNA methylase (ambiguous); DNA methyltransferase (ambiguous); DNA transmethylase (ambiguous); DNA-cytosine 5-methylase; DNA-cytosine methyltransferase; HpaII methylase; HpaII' methylase; M.BsuRIa; M.BsuRIb; Type II DNA methylase; cytosine 5-methyltransferase; cytosine DNA methylase; cytosine DNA methyltransferase; cytosine-specific DNA methyltransferase; deoxyribonucleate methylase (ambiguous); deoxyribonucleate methyltransferase (ambiguous); deoxyribonucleic (cytosine-5-)-methyltransferase; deoxyribonucleic acid (cytosine-5-)-methyltransferase; deoxyribonucleic acid methylase (ambiguous); deoxyribonucleic acid methyltransferase (ambiguous); deoxyribonucleic acid modification methylase (ambiguous); deoxyribonucleic methylase (ambiguous); methylphosphotriester-DNA methyltransferase (ambiguous); modification methylase (ambiguous); restriction-modification system (ambiguous); site-specific DNA-methyltransferase (cytosine-specific); DNA-(cytosine C5)-methylase

Systematic name: S-adenosyl-L-methionine:DNA (cytosine-5-)-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9037-42-7

References:

1. Gold, M. and Hurwitz, J. The enzymatic methylation of ribonucleic acid and deoxyribonucleic acid. V. Purification and properties of the deoxyribonucleic acid-methylating activity of Escherichia coli. J. Biol. Chem. 239 (1964) 3858-2865.

2. Kalousek, F. and Morris, N.R. The purification and properties of deoxyribonucleic acid methylase from rat spleen. J. Biol. Chem. 244 (1969) 1157-1163. [PMID: 4975067]

3. Roy, P.H. and Weissbach, A. DNA methylase from HeLa cell nuclei. Nucleic Acids Res. 2 (1975) 1669-1684. [PMID: 1187340]

4. Simon, D., Grunert, F., Acken, U.Y., Döring, H.P. and Kröger, H. DNA-methylase from regenerating rat liver: purification and characterisation. Nucleic Acids Res. 5 (1978) 2153-2167. [PMID: 673848]

5. Sneider, T.W., Teague, W.M. and Rogachewsky, L.M. S-Adenosylmethionine: DNA-cytosine 5-methyltransferase from a Novikoff rat hepatoma cell line. Nucleic Acids Res. 2 (1975) 1685-1700. [PMID: 171625]

6. Turnbull, J.F. and Adams, R.L.P. DNA methylase: purification from ascites cells and the effect of various DNA substrates on its activity. Nucleic Acids Res. 3 (1976) 677-695. [PMID: 131936]

7. Kessler, C. and Manta, V. Specificity of restriction endonucleases and DNA modification methyltransferases: a review. Gene 92 (1990) 1-248. [PMID: 91032997]

8. Roberts, R.J. Restriction enzymes and their isoschizomers. Nucleic Acids Res. 18 (1990) 2331-2365. [PMID: 2159140]

9. Yuan, R. Structure and mechanism of multifunctional restriction endonucleases. Annu. Rev. Biochem. 50 (1981) 285-319. [PMID: 6267988]

[EC 2.1.1.37 created 1972, (EC 2.1.1.73 incorporated 2003), modified 2003]

EC 2.1.1.38

Accepted name: O-demethylpuromycin O-methyltransferase

Reaction: S-adenosyl-L-methionine + O-demethylpuromycin = S-adenosyl-L-homocysteine + puromycin

Other name(s): O-demethylpuromycin methyltransferase

Systematic name: S-adenosyl-L-methionine:O-demethylpuromycin O-methyltransferase

Comments: Puromycin is the antibiotic derived from N6-dimethyladenosine by replacing the 3'-hydroxy group with an amino group and acylating this with 4-O-methyltyrosine.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37257-04-8

References:

1. Rao, M.M., Rebello, P.F. and Pogell, B.M. Biosynthesis of puromycin in Streptomyces alboniger. Enzymatic methylation of O-demethylpuromycin. J. Biol. Chem. 244 (1969) 112-118. [PMID: 5773275]

[EC 2.1.1.38 created 1972]

EC 2.1.1.39

Accepted name: inositol 3-methyltransferase

Reaction: S-adenosyl-L-methionine + myo-inositol = S-adenosyl-L-homocysteine + 1D-3-O-methyl-myo-inositol

For diagram click here.

Other name(s): inositol L-1-methyltransferase; myo-inositol 1-methyltransferase; S-adenosylmethionine:myo-inositol 1-methyltransferase; myo-inositol 1-O-methyltransferase (name based on 1L-numbering system and not 1D-numbering); S-adenosyl-L-methionine:myo-inositol 1-O-methyltransferase

Systematic name: S-adenosyl-L-methionine:1D-myo-inositol 3-O-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37257-05-9

References:

1. Hofmann, H., Wagner, I. and Hoffmann-Ostenhof, O. Untersuchungen über die Biosynthese der Cyclite. XXIV. Über ein lösliches Enzym aus Vinca rosea, das myo-Inosit zu L-Bornesit methyliert. Hoppe-Seyler's Z. Physiol. Chem. 350 (1969) 1465-1468. [PMID: 5362621]

[EC 2.1.1.39 created 1972, modified 2002]

EC 2.1.1.40

Accepted name: inositol 1-methyltransferase

Reaction: S-adenosyl-L-methionine + myo-inositol = S-adenosyl-L-homocysteine + 1D-1-O-methyl-myo-inositol

For diagram click here.

Other name(s): inositol D-1-methyltransferase; S-adenosylmethionine:myo-inositol 3-methyltransferase; myo-inositol 3-O-methyltransferase; inositol 3-O-methyltransferase (name based on 1L-numbering system and not 1D-numbering); S-adenosyl-L-methionine:myo-inositol 3-O-methyltransferase

Systematic name: S-adenosyl-L-methionine:1D-myo-inositol 1-O-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37257-06-0

References:

1 .Wagner, I., Hofmann, H. and Hoffmann-Ostenhof, O. Untersuchungen über die Biosynthese der Cyclite. XXIII. Über ein lösliches Enzym aus Erbsenkeimlingen, das myo-Inosit zu D-Bornesit methyliert. Hoppe-Seyler's Z. Physiol. Chem. 350 (1969) 1460-1464. [PMID: 5362620]

[EC 2.1.1.40 created 1972, modified 2002]

EC 2.1.1.41

Accepted name: sterol 24-C-methyltransferase

Reaction: S-adenosyl-L-methionine + 5α-cholesta-8,24-dien-3β-ol = S-adenosyl-L-homocysteine + 24-methylene-5α-cholest-8-en-3β-ol

For diagram click here.

Glossary entries:
desmosterol = cholesta-5,24-dien-3β-ol
zymostrol = 5α-cholesta-8,24-dien-3β-ol

Other name(s): δ24-methyltransferase; δ24-sterol methyltransferase; zymosterol-24-methyltransferase; S-adenosyl-4-methionine:sterol δ24-methyltransferase; SMT1; 24-sterol C-methyltransferase; S-adenosyl-L-methionine:δ24(23)-sterol methyltransferase; phytosterol methyltransferase

Systematic name: S-adenosyl-L-methionine:zymosterol 24-C-methyltransferase

Comments: Requires glutathione. Acts on a range of sterols with a 24(25)-double bond in the sidechain. While zymosterol is the preferred substrate it also acts on desmosterol, 5α-cholesta-7,24-dien-3β-ol, 5α-cholesta-5,7,24-trien-3β-ol, 4α-methylzymosterol and others. S-Adenosyl-L-methionine attacks the Si-face of the 24(25) double bond and the C-24 hydrogen is transferred to C-25 on the Re face of the double bond.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37257-07-1

References:

1. Moore, J.T., Jr. and Gaylor, J.L. Isolation and purification of an S-adenosylmethionine: δ24-sterol methyltransferase from yeast. J. Biol. Chem. 244 (1969) 6334-6340. [PMID: 5354959]

2. Venkatramesh, M., Guo, D., Jia, Z. and Nes, W.D. Mechanism and structural requirements for transformations of substrates by the S-adenosyl-L-methionine:δ24(25)-sterol methyl transferase enzyme from Saccharomyces cerevisiae. Biochim. Biophys. Acta 1299 (1996) 313-324. [PMID: 8597586]

3. Tong, Y., McCourt, B.S., Guo, D., Mangla, A.T., Zhou, W.X., Jenkins, M.D., Zhou, W., Lopez, M. and Nes, W.D., Stereochemical features of C-methylation on the path to δ24(28)-methylene and δ24(28)-ethylidene sterols: studies on the recombinant phytosterol methyl transferase from Arabidopsis thaliana. Tetrahedron Lett. 38 (1997) 6115-6118.

4. Bouvier-Navé, P., Husselstein, T. and Benveniste, P. Two families of sterol methyltransferases are involved in the first and the second methylation steps of plant biosynthesis. Eur. J. Biochem. 256 (1998) 88-96. [PMID: 9746350]

5. Nes, W.D., McCourt, B.S., Zhou, W., Ma, J., Marshall, J.A., Peek, L.A. and Brennan, M. Overexpression, purification, and stereochemical studies of the recombinant S-adenosyl-L-methionine:δ24(25)- to δ24(28)-sterol methyl transferase enzyme from Saccharomyces cerevisiae sterol methyl transferase. Arch. Biochem. Biophys. 353 (1998) 297-311. [PMID: 9606964]

[EC 2.1.1.41 created 1972, modified 2001]

EC 2.1.1.42

Accepted name: flavone 3'-O-methyltransferase

Reaction: S-adenosyl-L-methionine + 3'-hydroxyflavone = S-adenosyl-L-homocysteine + 3'-methoxyflavone

For diagram of reaction click here

Other name(s): o-dihydric phenol methyltransferase; luteolin methyltransferase; luteolin 3'-O-methyltransferase; o-diphenol m-O-methyltransferase; o-dihydric phenol meta-O-methyltransferase; S-adenosylmethionine:flavone/flavonol 3'-O-methyltransferase; quercetin 3'-O-methyltransferase

Systematic name: S-adenosyl-L-methionine:3'-hydroxyflavone 3'-O-methyltransferase

Comments: The enzyme prefers flavones with vicinal 3',4'-dihydroxyl groups.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 37205-55-3

References:

1. Ebel, J., Hahlbrock, K. and Grisebach, H. Purification and properties of an o-dihydricphenol meta-O-methyltransferase from cell suspension cultures of parsley and its relation to flavonoid biosynthesis. Biochim. Biophys. Acta 268 (1972) 313-326. [PMID: 5026305]

2. Muzac, I., Wang, J., Anzellotti, D., Zhang, H. and Ibrahim, R.K. Functional expression of an Arabidopsis cDNA clone encoding a flavonol 3'-O-methyltransferase and characterization of the gene product. Arch. Biochem. Biophys. 375 (2000) 385-388. [PMID: 10700397]

3. Poulton, J.E., Hahlbrock, K. and Grisebach, H. O-Methylation of flavonoid substrates by a partially purified enzyme from soybean cell suspension cultures. Arch. Biochem. Biophys. 180 (1977) 543-549. [PMID: 18099]

4. Kim, B.G., Lee, H.J., Park, Y., Lim, Y. and Ahn, J.H. Characterization of an O-methyltransferase from soybean. Plant Physiol. Biochem. 44 (2006) 236-241. [PMID: 16777424]

5. Lee, Y.J., Kim, B.G., Chong, Y., Lim, Y. and Ahn, J.H. Cation dependent O-methyltransferases from rice. Planta 227 (2008) 641-647. [PMID: 17943312]

[EC 2.1.1.42 created 1976, modified 2011]

EC 2.1.1.43

Accepted name: histone-lysine N-methyltransferase

Reaction: S-adenosyl-L-methionine + histone L-lysine = S-adenosyl-L-homocysteine + histone N6-methyl-L-lysine

Other name(s): protein methylase III; protein methylase 3; protein (lysine) methyltransferase; protein methyltransferase II; protein-lysine N-methyltransferase; histone H1-specific S-adenosylmethionine:protein-lysine N-methyltransferase

Systematic name: S-adenosyl-L-methionine:histone-L-lysine N6-methyltransferase

Comments: One of a group of enzymes methylating proteins; see also EC 2.1.1.59 [cytochrome-c]-lysine N-methyltransferase and EC 2.1.1.60 calmodulin-lysine N-methyltransferase.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9055-08-7

References:

1. Paik, W.K. and Kim, S. Solubilization and partial purification of protein methylase 3 from calf thymus nuclei. J. Biol. Chem. 245 (1970) 6010-6015. [PMID: 5484460]

2. Venkatesan, M. and McManus, I.R. Partial purification and characterization of a protein lysine methyltransferase from plasmodia of Physarum polycephalum. Biochemistry 18 (1979) 5365-5371. [PMID: 391266]

[EC 2.1.1.43 created 1976, modified 1982, modified 1983]

EC 2.1.1.44

Accepted name: L-histidine Nα-methyltransferase

Reaction: 3 S-adenosyl-L-methionine + L-histidine = 3 S-adenosyl-L-homocysteine + hercynine (overall reaction)
(1a) S-adenosyl-L-methionine + L-histidine = S-adenosyl-L-homocysteine + Nα-methyl-L-histidine
(1b) S-adenosyl-L-methionine + Nα-methyl-L-histidine = S-adenosyl-L-homocysteine + Nα,Nα-dimethyl-L-histidine
(1c) S-adenosyl-L-methionine + Nα,Nα-dimethyl-L-histidine = S-adenosyl-L-homocysteine + hercynine

For diagram of reaction click here.

Glossary: hercynine = Nα,Nα,Nα-trimethyl-L-histidine

Other name(s): dimethylhistidine N-methyltransferase; dimethylhistidine methyltransferase; histidine-α-N-methyltransferase; S-adenosyl-L-methionine:α-N,α-N-dimethyl-L-histidine α-N-methyltransferase; S-adenosyl-L-methionine:Nα,Nα-dimethyl-L-histidine Nα-methyltransferase

Systematic name: S-adenosyl-L-methionine:L-histidine Nα-methyltransferase (hercynine-forming)

Comments: Part of the biosynthetic pathway of ergothioneine.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 62213-53-0

References:

1. Ishikawa, Y. and Melville, D.B. The enzymatic α-N-methylation of histidine. J. Biol. Chem. 245 (1970) 5967-5973. [PMID: 5484456]

2. Seebeck, F.P. In vitro reconstitution of mycobacterial ergothioneine biosynthesis. J. Am. Chem. Soc. 132 (2010) 6632-6633. [PMID: 20420449]

[EC 2.1.1.44 created 1976, modified 2013]

EC 2.1.1.45

Accepted name: thymidylate synthase

Reaction: 5,10-methylenetetrahydrofolate + dUMP = dihydrofolate + dTMP

For diagram of reaction click here.

Other name(s): dTMP synthase; thymidylate synthetase; methylenetetrahydrofolate:dUMP C-methyltransferase; TMP synthetase

Systematic name: 5,10-methylenetetrahydrofolate:dUMP C-methyltransferase

Links to other databases: BRENDA, EXPASY, GTD, KEGG, Metacyc, PDB, CAS registry number: 9031-61-2

References:

1. Blakley, R.L. The biosynthesis of thymidylic acid. IV. Further studies on thymidylate synthase. J. Biol. Chem. 238 (1963) 2113-2118.

2. Lockshin, A., Moran, R.G. and Danenberg, P.V. Thymidylate synthetase purified to homogeneity from human leukemic cells. Proc. Natl. Acad. Sci. USA 76 (1979) 750-754. [PMID: 34155]

3. Slavik, K. and Slavikova, V. Purification of thymidylate synthetase from enzyme-poor sources by affinity chromatography. Methods Enzymol. 66 (1980) 709-723. [PMID: 6990200]

4. Wahba, A.J. and Friedkin, M. The enzymatic synthesis of thymidylate. I. Early steps in the purification of thymidylate synthetase of Escherichia coli. J. Biol. Chem. 237 (1962) 3794-3801.

[EC 2.1.1.45 created 1976]

EC 2.1.1.46

Accepted name: isoflavone 4'-O-methyltransferase

Reaction: S-adenosyl-L-methionine + a 4'-hydroxyisoflavone = S-adenosyl-L-homocysteine + a 4'-methoxyisoflavone

For diagram of reaction click here or click here

Other name(s): 4'-hydroxyisoflavone methyltransferase; isoflavone methyltransferase; isoflavone O-methyltransferase

Systematic name: S-adenosyl-L-methionine:4'-hydroxyisoflavone 4'-O-methyltransferase

Comments: Requires Mg2+ for activity. The enzyme catalyses the methylation of daidzein and genistein. It does not methylate naringenin, apigenin, luteolin or kaempferol.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 55071-80-2

References:

1. Wengenmayer, H., Ebel, J. and Grisebach, H. Purification and properties of a S-adenosylmethionine: isoflavone 4'-O-methyltransferase from cell suspension cultures of Cicer arietinum L. Eur. J. Biochem. 50 (1974) 135-143. [PMID: 4452353]

[EC 2.1.1.46 created 1976, modified 2011]

EC 2.1.1.47

Accepted name: indolepyruvate C-methyltransferase

Reaction: S-adenosyl-L-methionine + (indol-3-yl)pyruvate = S-adenosyl-L-homocysteine + (R)-3-(indol-3-yl)-2-oxobutanoate

Other name(s): ind1 (gene name); indolepyruvate methyltransferase; indolepyruvate 3-methyltransferase; indolepyruvic acid methyltransferase; S-adenosyl-L-methionine:indolepyruvate C-methyltransferase

Systematic name: S-adenosyl-L-methionine:(indol-3-yl)pyruvate C-methyltransferase

Comments: The enzyme, characterized from the bacterium Streptomyces griseus, is involved in the biosynthesis of the antibacterial drug indolmycin.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 54576-88-4

References:

1. Hornemann, U., Speedie, M.K., Hurley, L.H. and Floss, H.G. Demonstration of a C-methylating enzyme in cell free extracts of indolmycin-producing Streptomyces griseus. Biochem. Biophys. Res. Commun. 39 (1970) 594-599. [PMID: 5490210]

2. Hornemann, U., Hurley, L.H., Speedie, M.K. and Floss, H.G. The biosynthesis of indolmycin. J. Am. Chem. Soc. 93 (1971) 3028-3035. [PMID: 5095271]

3. Speedie, M.K., Hornemann, U. and Floss, H.G. Isolation and characterization of tryptophan transaminase and indolepyruvate C-methyltransferase. Enzymes involved in indolmycin biosynthesis in Streptomyces griseus. J. Biol. Chem. 250 (1975) 7819-7825. [PMID: 809439]

4. Du, Y.L., Alkhalaf, L.M. and Ryan, K.S. In vitro reconstitution of indolmycin biosynthesis reveals the molecular basis of oxazolinone assembly. Proc. Natl. Acad. Sci. USA 112 (2015) 2717-2722. [PMID: 25730866]

[EC 2.1.1.47 created 1976, modified 2016]

[EC 2.1.1.48 Transferred entry: rRNA (adenine-N6-)-methyltransferase. Now covered by EC 2.1.1.181 [23S rRNA (adenine1618-N6)-methyltransferase], EC 2.1.1.182 [16S rRNA adenine1518-N6/adenine1519-N6)-dimethyltransferase], EC 2.1.1.183 [18S rRNA (adenine1779-N6/adenine1780-N6)-dimethyltransferase] and EC 2.1.1.184 [23S rRNA (adenine2085-N6)-dimethyltransferase] (EC 2.1.1.48 created 1976, deleted 2010)]

EC 2.1.1.49

Accepted name: amine N-methyltransferase

Reaction: S-adenosyl-L-methionine + an amine = S-adenosyl-L-homocysteine + a methylated amine

Other name(s): nicotine N-methyltransferase; tryptamine N-methyltransferase; arylamine N-methyltransferase; tryptamine methyltransferase

Systematic name: S-adenosyl-L-methionine:amine N-methyltransferase

Comments: An enzyme of very broad specificity; many primary, secondary and tertiary amines can act as acceptors, including tryptamine, aniline, nicotine and a variety of drugs and other xenobiotics.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 51377-47-0, 111694-10-1

References:

1. Ansher, S.S. and Jakoby, W.B. Amine N-methyltransferases from rabbit liver. J. Biol. Chem. 261 (1986) 3996-4001. [PMID: 3949799]

2. Crooks, P.A., Godin, C.S., Damani, L.A., Ansher, S.S. and Jakoby, W.B. Formation of quaternary amines by N-methylation of azaheterocycles with homogeneous amine N-methyltransferases. Biochem. Pharmacol. 37 (1988) 1673-1677. [PMID: 3377829]

[EC 2.1.1.49 created 1976, modified 1990 (EC 2.1.1.81 created 1989, incorporated 1990)]

EC 2.1.1.50

Accepted name: loganate O-methyltransferase

Reaction: S-adenosyl-L-methionine + loganate = S-adenosyl-L-homocysteine + loganin

For diagram click here.

Other name(s): loganate methyltransferase; S-adenosyl-L-methionine:loganic acid methyltransferase

Systematic name: S-adenosyl-L-methionine:loganate 11-O-methyltransferase

Comments: Also acts on secologanate. Methylates the 11-carboxy group of the monoterpenoid loganate.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 39391-10-1

References:

1. Madyastha, K.M., Guarnaccia, R., Baxter, C. and Coscia, C.J. S-Adenosyl-L-methionine: loganic acid methyltransferase. A carboxyl-alkylating enzyme from Vinca rosea. J. Biol. Chem. 248 (1973) 2497-2501. [PMID: 4698228]

[EC 2.1.1.50 created 1976]


Continued with EC 2.1.1.51 to EC 2.1.1.100
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