Enzyme Nomenclature

EC 2.1.1 (continued)

Methyltransferases

Continued from:
EC 2.1.1.1 to EC 2.1.1.50
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 See separate file for EC 2.1.1.301 to EC 2.1.1.396.

Contents

EC 2.1.1.251 methylated-thiol—coenzyme M methyltransferase
EC 2.1.1.252 tetramethylammonium—corrinoid protein Co-methyltransferase
EC 2.1.1.253 [methyl-Co(III) tetramethylammonium-specific corrinoid protein]—coenzyme M methyltransferase
EC 2.1.1.254 erythromycin 3"-O-methyltransferase
EC 2.1.1.255 geranyl diphosphate 2-C-methyltransferase
EC 2.1.1.256 tRNA (guanine6-N2)-methyltransferase
EC 2.1.1.257 tRNA (pseudouridine54-N1)-methyltransferase
EC 2.1.1.258 5-methyltetrahydrofolate:corrinoid—iron-sulfur protein Co-methyltransferase
EC 2.1.1.259 [fructose-bisphosphate aldolase]-lysine N-methyltransferase
EC 2.1.1.260 rRNA small subunit pseudouridine methyltransferase Nep1
EC 2.1.1.261 4-dimethylallyltryptophan N-methyltransferase
EC 2.1.1.262 squalene methyltransferase
EC 2.1.1.263 botryococcene C-methyltransferase
EC 2.1.1.264 23S rRNA (guanine2069-N7)-methyltransferase
EC 2.1.1.265 tellurite methyltransferase
EC 2.1.1.266 23S rRNA (adenine2030-N6)-methyltransferase
EC 2.1.1.267 flavonoid 3',5'-methyltransferase
EC 2.1.1.268 tRNAThr (cytosine32-N3)-methyltransferase
EC 2.1.1.269 dimethylsulfoniopropionate demethylase
EC 2.1.1.270 (+)-6a-hydroxymaackiain 3-O-methyltransferase
EC 2.1.1.271 cobalt-precorrin-4 methyltransferase
EC 2.1.1.272 cobalt-factor III methyltransferase
EC 2.1.1.273 benzoate O-methyltransferase
EC 2.1.1.274 salicylate 1-O-methyltransferase
EC 2.1.1.275 gibberellin A9 O-methyltransferase
EC 2.1.1.276 gibberellin A4 carboxyl methyltransferase
EC 2.1.1.277 anthranilate O-methyltransferase
EC 2.1.1.278 indole-3-acetate O-methyltransferase
EC 2.1.1.279 trans-anol O-methyltransferase
EC 2.1.1.280 selenocysteine Se-methyltransferase
EC 2.1.1.281 phenylpyruvate C3-methyltransferase
EC 2.1.1.282 tRNAPhe 7-[(3-amino-3-carboxypropyl)-4-demethylwyosine37-N4]-methyltransferase
EC 2.1.1.283 emodin O-methyltransferase
EC 2.1.1.284 8-demethylnovobiocic acid C8-methyltransferase
EC 2.1.1.285 demethyldecarbamoylnovobiocin O-methyltransferase
EC 2.1.1.286 25S rRNA (adenine2142-N1)-methyltransferase
EC 2.1.1.287 25S rRNA (adenine645-N1)-methyltransferase
EC 2.1.1.288 aklanonic acid methyltransferase
EC 2.1.1.289 cobalt-precorrin-7 (C5)-methyltransferase
EC 2.1.1.290 tRNAPhe [7-(3-amino-3-carboxypropyl)wyosine37-O]-methyltransferase
EC 2.1.1.291 (R,S)-reticuline 7-O-methyltransferase
EC 2.1.1.292 carminomycin 4-O-methyltransferase
EC 2.1.1.293 6-hydroxytryprostatin B O-methyltransferase
EC 2.1.1.294 3-O-phospho-polymannosyl GlcNAc-diphospho-ditrans,octacis-undecaprenol 3-phospho-methyltransferase
EC 2.1.1.295 2-methyl-6-phytyl-1,4-hydroquinone methyltransferase
EC 2.1.1.296 methyltransferase cap2 (28 February 2014)
EC 2.1.1.297 peptide chain release factor N5-glutamine methyltransferase
EC 2.1.1.298 ribosomal protein L3 N5-glutamine methyltransferase
EC 2.1.1.299 protein N-terminal monomethyltransferase
EC 2.1.1.300 pavine N-methyltransferase

See the following files for:
EC 2.1.1.301 to EC 2.1.1.396

Entries

EC 2.1.1.251

Accepted name: methylated-thiol—coenzyme M methyltransferase

Reaction: methanethiol + CoM = methyl-CoM + hydrogen sulfide (overall reaction)
(1a) methanethiol + a [Co(I) methylated--thiol-specific corrinoid protein] = a [methyl-Co(III) methylated-thiol-specific corrinoid protein] + hydrogen sulfide
(1b) a [methyl-Co(III) methylated-thiol-specific corrinoid protein] + coenzyme M = methyl-CoM + a [Co(I) methylated-thiol-specific corrinoid protein]

Glossary: CoM = coenzyme M = 2-sulfanylethane-1-sulfonate = 2-mercaptoethanesulfonate (deprecated)

Other name(s): mtsA (gene name)

Systematic name: methylated-thiol:coenzyme M methyltransferase

Comments: The enzyme, which is involved in methanogenesis from methylated thiols, such as methane thiol, dimethyl sulfide, and 3-S-methylmercaptopropionate, catalyses two successive steps - the transfer of a methyl group from the substrate to the cobalt cofactor of a methylated-thiol-specific corrinoid protein (MtsB), and the subsequent transfer of the methyl group from the corrinoid protein to coenzyme M. With most other methanogenesis substrates this process is carried out by two different enzymes (for example, EC 2.1.1.90, methanol—corrinoid protein Co-methyltransferase, and EC 2.1.1.246, methylated methanol-specific corrinoid protein:coenzyme M methyltransferase). The cobalt is oxidized during methylation from the Co(I) state to the Co(III) state, and is reduced back to the Co(I) form during demethylation.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Paul, L. and Krzycki, J.A. Sequence and transcript analysis of a novel Methanosarcina barkeri methyltransferase II homolog and its associated corrinoid protein homologous to methionine synthase. J. Bacteriol. 178 (1996) 6599-6607. [PMID: 8932317]

2. Tallant, T.C. and Krzycki, J.A. Methylthiol:coenzyme M methyltransferase from Methanosarcina barkeri, an enzyme of methanogenesis from dimethylsulfide and methylmercaptopropionate. J. Bacteriol. 179 (1997) 6902-6911. [PMID: 9371433]

3. Tallant, T.C., Paul, L. and Krzycki, J.A. The MtsA subunit of the methylthiol:coenzyme M methyltransferase of Methanosarcina barkeri catalyses both half-reactions of corrinoid-dependent dimethylsulfide: coenzyme M methyl transfer. J. Biol. Chem. 276 (2001) 4485-4493. [PMID: 11073950]

[EC 2.1.1.251 created 2012]

EC 2.1.1.252

Accepted name: tetramethylammonium—corrinoid protein Co-methyltransferase

Reaction: tetramethylammonium + a [(Co(I) tetramethylammonium-specific corrinoid protein] = a [methyl-Co(III) tetramethylammonium-specific corrinoid protein] + trimethylamine

Other name(s): mtqB (gene name); tetramethylammonium methyltransferase

Systematic name: tetramethylammonium:5-hydroxybenzimidazolylcobamide Co-methyltransferase

Comments: The enzyme, which catalyses the transfer of a methyl group from tetramethylammonium to a tetramethylammonium-specific corrinoid protein (MtqC), is involved in methanogenesis from tetramethylammonium. 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 2.1.1.253, methylated tetramethylammonium-specific corrinoid protein:coenzyme M methyltransferase.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Asakawa, S., Sauer, K., Liesack, W. and Thauer, R.K. Tetramethylammonium:coenzyme M methyltransferase system from methanococcoides s. Arch. Microbiol. 170 (1998) 220-226. [PMID: 9732435]

[EC 2.1.1.252 created 2012]

EC 2.1.1.253

Accepted name: [methyl-Co(III) tetramethylammonium-specific corrinoid protein]—coenzyme M methyltransferase

Reaction: a [methyl-Co(III) tetramethylammonium-specific corrinoid protein] + CoM = methyl-CoM + a [Co(I) tetramethylammonium-specific corrinoid protein]

Glossary: CoM = coenzyme M = 2-sulfanylethane-1-sulfonate = 2-mercaptoethanesulfonate (deprecated)

Other name(s): methyltransferase 2 (ambiguous); mtqA (gene name)

Systematic name: methylated tetramethylammonium-specific corrinoid protein:Coenzyme M methyltransferase

Comments: The enzyme, which is involved in methanogenesis from tetramethylammonium, catalyses the transfer of a methyl group from a corrinoid protein (see EC 2.1.1.252, tetramethylammonium—corrinoid protein Co-methyltransferase), where it is bound to the cobalt cofactor, to coenzyme M, forming the substrate for EC 2.8.4.1, coenzyme-B sulfoethylthiotransferase, the enzyme that catalyses the final step in methanogenesis.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Asakawa, S., Sauer, K., Liesack, W. and Thauer, R.K. Tetramethylammonium:coenzyme M methyltransferase system from methanococcoides s. Arch. Microbiol. 170 (1998) 220-226. [PMID: 9732435]

[EC 2.1.1.253 created 2012]

EC 2.1.1.254

Accepted name: erythromycin 3"-O-methyltransferase

Reaction: (1) S-adenosyl-L-methionine + erythromycin C = S-adenosyl-L-homocysteine + erythromycin A
(2) S-adenosyl-L-methionine + erythromycin D = S-adenosyl-L-homocysteine + erythromycin B

For diagram of reaction click here.

Other name(s): EryG

Systematic name: S-adenosyl-L-methionine:erythromycin C 3"-O-methyltransferase

Comments: The enzyme methylates the 3 position of the mycarosyl moiety of erythromycin C, forming the most active form of the antibiotic, erythromycin A. It can also methylate the precursor erythromycin D, forming erythromycin B, which is then converted to erythromycin A by EC 1.14.13.154, erythromycin 12-hydroxylase.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Paulus, T.J., Tuan, J.S., Luebke, V.E., Maine, G.T., DeWitt, J.P. and Katz, L. Mutation and cloning of eryG, the structural gene for erythromycin O-methyltransferase from Saccharopolyspora erythraea, and expression of eryG in Escherichia coli. J. Bacteriol. 172 (1990) 2541-2546. [PMID: 2185226]

2. Summers, R.G., Donadio, S., Staver, M.J., Wendt-Pienkowski, E., Hutchinson, C.R. and Katz, L. Sequencing and mutagenesis of genes from the erythromycin biosynthetic gene cluster of Saccharopolyspora erythraea that are involved in L-mycarose and D-desosamine production. Microbiology 143 (1997) 3251-3262. [PMID: 9353926]

[EC 2.1.1.254 created 2012]

EC 2.1.1.255

Accepted name: geranyl diphosphate 2-C-methyltransferase

Reaction: S-adenosyl-L-methionine + geranyl diphosphate = S-adenosyl-L-homocysteine + (E)-2-methylgeranyl diphosphate

For diagram of reaction click here and mechanism click here.

Other name(s): SCO7701; GPP methyltransferase; GPPMT; 2-methyl-GPP synthase; MGPPS; geranyl pyrophosphate methyltransferase

Systematic name: S-adenosyl-L-methionine:geranyl-diphosphate 2-C-methyltransferase

Comments: This enzyme, along with EC 4.2.3.118, 2-methylisoborneol synthase, produces 2-methylisoborneol, an odiferous compound produced by soil microorganisms with a strong earthy/musty odour.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Wang, C.M. and Cane, D.E. Biochemistry and molecular genetics of the biosynthesis of the earthy odorant methylisoborneol in Streptomyces coelicolor. J. Am. Chem. Soc. 130 (2008) 8908-8909. [PMID: 18563898]

2. Ariyawutthiphan, O., Ose, T., Tsuda, M., Gao, Y., Yao, M., Minami, A., Oikawa, H. and Tanaka, I. Crystallization and preliminary X-ray crystallographic study of a methyltransferase involved in 2-methylisoborneol biosynthesis in Streptomyces lasaliensis. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 67 (2011) 417-420. [PMID: 21393856]

3. Komatsu, M., Tsuda, M., Omura, S., Oikawa, H. and Ikeda, H. Identification and functional analysis of genes controlling biosynthesis of 2-methylisoborneol. Proc. Natl. Acad. Sci. USA 105 (2008) 7422-7427. [PMID: 18492804]

4. Giglio, S., Chou, W.K., Ikeda, H., Cane, D.E. and Monis, P.T. Biosynthesis of 2-methylisoborneol in cyanobacteria. Environ. Sci. Technol. 45 (2011) 992-998. [PMID: 21174459]

[EC 2.1.1.255 created 2012]

EC 2.1.1.256

Accepted name: tRNA (guanine6-N2)-methyltransferase

Reaction: S-adenosyl-L-methionine + guanine6 in tRNA = S-adenosyl-L-homocysteine + N2-methylguanine6 in tRNA

Other name(s): methyltransferase Trm14; m2G6 methyltransferase

Systematic name: S-adenosyl-L-methionine:tRNA (guanine6-N2)-methyltransferase

Comments: The enzyme specifically methylates guanine6 at N2 in tRNA.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Menezes, S., Gaston, K.W., Krivos, K.L., Apolinario, E.E., Reich, N.O., Sowers, K.R., Limbach, P.A. and Perona, J.J. Formation of m2G6 in Methanocaldococcus jannaschii tRNA catalyzed by the novel methyltransferase Trm14. Nucleic Acids Res. 39 (2011) 7641-7655. [PMID: 21693558]

[EC 2.1.1.256 created 2012]

EC 2.1.1.257

Accepted name: tRNA (pseudouridine54-N1)-methyltransferase

Reaction: S-adenosyl-L-methionine + pseudouridine54 in tRNA = S-adenosyl-L-homocysteine + N1-methylpseudouridine54 in tRNA

Other name(s): TrmY; m1Ψ methyltransferase

Systematic name: S-adenosyl-L-methionine:tRNA (pseudouridine54-N1)-methyltransferase

Comments: While this archaeal enzyme is specific for the 54 position and does not methylate pseudouridine at position 55, the presence of pseudouridine at position 55 is necessary for the efficient methylation of pseudouridine at position 54 [2,3].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Chen, H.Y. and Yuan, Y.A. Crystal structure of Mj1640/DUF358 protein reveals a putative SPOUT-class RNA methyltransferase. J. Mol. Cell. Biol. 2 (2010) 366-374. [PMID: 21098051]

2. Wurm, J.P., Griese, M., Bahr, U., Held, M., Heckel, A., Karas, M., Soppa, J. and Wohnert, J. Identification of the enzyme responsible for N1-methylation of pseudouridine 54 in archaeal tRNAs. RNA 18 (2012) 412-420. [PMID: 22274954]

3. Chatterjee, K., Blaby, I.K., Thiaville, P.C., Majumder, M., Grosjean, H., Yuan, Y.A., Gupta, R. and de Crecy-Lagard, V. The archaeal COG1901/DUF358 SPOUT-methyltransferase members, together with pseudouridine synthase Pus10, catalyze the formation of 1-methylpseudouridine at position 54 of tRNA. RNA 18 (2012) 421-433. [PMID: 22274953]

[EC 2.1.1.257 created 2012]

EC 2.1.1.258

Accepted name: 5-methyltetrahydrofolate—corrinoid/iron-sulfur protein Co-methyltransferase

Reaction: a [methyl-Co(III) corrinoid Fe-S protein] + tetrahydrofolate = a [Co(I) corrinoid Fe-S protein] + 5-methyltetrahydrofolate

Other name(s): acsE (gene name)

Systematic name: 5-methyltetrahydrofolate:corrinoid/iron-sulfur protein methyltransferase

Comments: Catalyses the transfer of a methyl group from the N5 group of methyltetrahydrofolate to the 5-methoxybenzimidazolylcobamide cofactor of a corrinoid/Fe-S protein. Involved, together with EC 1.2.7.4, carbon-monoxide dehydrogenase (ferredoxin) and EC 2.3.1.169, CO-methylating acetyl-CoA synthase, in the reductive acetyl coenzyme A (Wood-Ljungdahl) pathway of autotrophic carbon fixation in various bacteria and archaea.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Roberts, D.L., Zhao, S., Doukov, T. and Ragsdale, S.W. The reductive acetyl coenzyme A pathway: sequence and heterologous expression of active methyltetrahydrofolate:corrinoid/iron-sulfur protein methyltransferase from Clostridium thermoaceticum. J. Bacteriol. 176 (1994) 6127-6130. [PMID: 7928975]

2. Doukov, T., Seravalli, J., Stezowski, J.J. and Ragsdale, S.W. Crystal structure of a methyltetrahydrofolate- and corrinoid-dependent methyltransferase. Structure 8 (2000) 817-830. [PMID: 10997901]

3. Doukov, T.I., Hemmi, H., Drennan, C.L. and Ragsdale, S.W. Structural and kinetic evidence for an extended hydrogen-bonding network in catalysis of methyl group transfer. Role of an active site asparagine residue in activation of methyl transfer by methyltransferases. J. Biol. Chem. 282 (2007) 6609-6618. [PMID: 17172470]

[EC 2.1.1.258 created 2012]

EC 2.1.1.259

Accepted name: [fructose-bisphosphate aldolase]-lysine N-methyltransferase

Reaction: 3 S-adenosyl-L-methionine + [fructose-bisphosphate aldolase]-L-lysine = 3 S-adenosyl-L-homocysteine + [fructose-bisphosphate aldolase]-N6,N6,N6-trimethyl-L-lysine

Other name(s): rubisco methyltransferase; ribulose-bisphosphate-carboxylase/oxygenase N-methyltransferase; ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit εN-methyltransferase; S-adenosyl-L-methionine:[3-phospho-D-glycerate-carboxy-lyase (dimerizing)]-lysine 6-N-methyltransferase

Systematic name: S-adenosyl-L-methionine:[fructose-bisphosphate aldolase]-lysine N6-methyltransferase

Comments: The enzyme methylates a conserved lysine in the C-terminal part of higher plant fructose-bisphosphate aldolase (EC 4.1.2.13). The enzyme from pea (Pisum sativum) also methylates Lys-14 in the large subunits of hexadecameric higher plant ribulose-bisphosphate-carboxylase (EC 4.1.1.39) [2], but that from Arabidopsis thaliana does not.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Magnani, R., Nayak, N.R., Mazarei, M., Dirk, L.M. and Houtz, R.L. Polypeptide substrate specificity of PsLSMT. A set domain protein methyltransferase. J. Biol. Chem. 282 (2007) 27857-27864. [PMID: 17635932]

2. Mininno, M., Brugiere, S., Pautre, V., Gilgen, A., Ma, S., Ferro, M., Tardif, M., Alban, C. and Ravanel, S. Characterization of chloroplastic fructose 1,6-bisphosphate aldolases as lysine-methylated proteins in plants. J. Biol. Chem. 287 (2012) 21034-21044. [PMID: 22547063]

[EC 2.1.1.259 created 2012]

EC 2.1.1.260

Accepted name: rRNA small subunit pseudouridine methyltransferase Nep1

Reaction: S-adenosyl-L-methionine + pseudouridine1191 in yeast 18S rRNA = S-adenosyl-L-homocysteine + N1-methylpseudouridine1191 in yeast 18S rRNA

Other name(s): Nep1; nucleolar essential protein 1

Systematic name: S-adenosyl-L-methionine:18S rRNA (pseudouridine1191-N1)-methyltransferase

Comments: This enzyme, which occurs in both prokaryotes and eukaryotes, recognizes specific pseudouridine residues (Ψ) in small subunits of ribosomal RNA based on the local RNA structure. It recognizes Ψ914 in 16S rRNA from the archaeon Methanocaldococcus jannaschii, Ψ1191 in yeast 18S rRNA, and Ψ1248 in human 18S rRNA.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Taylor, A.B., Meyer, B., Leal, B.Z., Kötter, P., Schirf, V., Demeler, B., Hart, P.J., Entian, K.-D. and Wöhnert, J. The crystal structure of Nep1 reveals an extended SPOUT-class methyltransferase fold and a pre-organized SAM-binding site. Nucleic Acids Res. 36 (2008) 1542-1554. [PMID: 18208838]

2. Wurm, J.P., Meyer, B., Bahr, U., Held, M., Frolow, O., Kötter, P., Engels, J.W., Heckel, A., Karas, M., Entian, K.-D. and Wöhnert, J. The ribosome assembly factor Nep1 responsible for Bowen-Conradi syndrome is a pseudouridine-N1-specific methyltransferase. Nucleic Acids Res. 38 (2010) 2387-2398. [PMID: 20047967]

3. Meyer, B., Wurm, J.P., Kötter, P., Leisegang, M.S., Schilling, V., Buchhaupt, M., Held, M., Bahr, U., Karas, M., Heckel, A., Bohnsack, M.T., Wöhnert, J. and Entian, K.-D. The Bowen-Conradi syndrome protein Nep1 (Emg1) has a dual role in eukaryotic ribosome biogenesis, as an essential assembly factor and in the methylation of Ψ1191 in yeast 18S rRNA. Nucleic Acids Res. 39 (2011) 1526-1537. [PMID: 20972225]

[EC 2.1.1.260 created 2012]

EC 2.1.1.261

Accepted name: 4-dimethylallyltryptophan N-methyltransferase

Reaction: S-adenosyl-L-methionine + 4-prenyl-L-tryptophan = S-adenosyl-L-homocysteine + 4-prenyl-L-abrine

For diagram of reaction click here.

Glossary: 4-prenyl-L-tryptophan = 4-(3-methylbut-2-enyl)-L-tryptophan = 4-dimethylallyl-L-tryptophan (ambiguous);
4-prenyl-L-abrine = 4-(3-methylbut-2-enyl)-L-abrine = 4-dimethylallyl-L-abrine (ambiguous)

Other name(s): fgaMT (gene name); easF (gene name)

Systematic name: S-adenosyl-L-methionine:4-(3-methylbut-2-enyl)-L-tryptophan N-methyltransferase

Comments: The enzyme catalyses a step in the pathway leading to biosynthesis of ergot alkaloids in certain fungi.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Rigbers, O. and Li, S.M. Ergot alkaloid biosynthesis in Aspergillus fumigatus. Overproduction and biochemical characterization of a 4-dimethylallyltryptophan N-methyltransferase. J. Biol. Chem. 283 (2008) 26859-26868. [PMID: 18678866]

[EC 2.1.1.261 created 2012]

EC 2.1.1.262

Accepted name: squalene methyltransferase

Reaction: 2 S-adenosyl-L-methionine + squalene = 2 S-adenosyl-L-homocysteine + 3,22-dimethyl-1,2,23,24-tetradehydro-2,3,22,23-tetrahydrosqualene (overall reaction)
(1a) S-adenosyl-L-methionine + squalene = S-adenosyl-L-homocysteine + 3-methyl-1,2-didehydro-2,3-dihydrosqualene
(1b) S-adenosyl-L-methionine + 3-methyl-1,2-didehydro-2,3-dihydrosqualene = S-adenosyl-L-homocysteine + 3,22-dimethyl-1,2,23,24-tetradehydro-2,3,22,23-tetrahydrosqualene

For diagram of reaction click here.

Other name(s): TMT-1; TMT-2

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

Comments: Two isoforms differing in their specificity were isolated from the green alga Botryococcus braunii BOT22. TMT-1 gave more of the dimethylated form whereas TMT2 gave more of the monomethylated form.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Niehaus, T.D., Kinison, S., Okada, S., Yeo, Y.S., Bell, S.A., Cui, P., Devarenne, T.P. and Chappell, J. Functional identification of triterpene methyltransferases from Botryococcus braunii race B. J. Biol. Chem. 287 (2012) 8163-8173. [PMID: 22241476]

[EC 2.1.1.262 created 2012]

EC 2.1.1.263

Accepted name: botryococcene C-methyltransferase

Reaction: 2 S-adenosyl-L-methionine + C30 botryococcene = 2 S-adenosyl-L-homocysteine + 3,20-dimethyl-1,2,21,22-tetradehydro-2,3,20,21-tetrahydrobotryococcene (overall reaction)
(1a) S-adenosyl-L-methionine + C30 botryococcene = S-adenosyl-L-homocysteine + 3-methyl-1,2-didehydro-2,3-dihydrobotryococcene
(1b) S-adenosyl-L-methionine + 3-methyl-1,2-didehydro-2,3-dihydrobotryococcene = S-adenosyl-L-homocysteine + 3,20-dimethyl-1,2,21,22-tetradehydro-2,3,20,21-tetrahydrobotryococcene
(2a) S-adenosyl-L-methionine + C30 botryococcene = S-adenosyl-L-homocysteine + 20-methyl-21,22-didehydro-20,21-dihydrobotryococcene
(2b) S-adenosyl-L-methionine + 20-methyl-21,22-didehydro-20,21-dihydrobotryococcene = S-adenosyl-L-homocysteine + 3,20-dimethyl-1,2,21,22-tetradehydro-2,3,20,21-tetrahydrobotryococcene

For diagram of reaction click here.

Glossary: C30 botryococcene = (10S,13R)-10-ethenyl-2,6,10,13,17,21-hexamethyldocosa-2,5,11,16,20-pentaene
3-methyl-1,2-didehydro-2,3-dihydrobotryococcene = showacene
20-methyl-21,22-didehydro-20,21-dihydrobotryococcene = isoshowacene

Other name(s): TMT-3

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

Comments: Isolated from the green alga Botryococcus braunii BOT22. Shows a very weak activity with squalene.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Niehaus, T.D., Kinison, S., Okada, S., Yeo, Y.S., Bell, S.A., Cui, P., Devarenne, T.P. and Chappell, J. Functional identification of triterpene methyltransferases from Botryococcus braunii race B. J. Biol. Chem. 287 (2012) 8163-8173. [PMID: 22241476]

[EC 2.1.1.263 created 2012]

EC 2.1.1.264

Accepted name: 23S rRNA (guanine2069-N7)-methyltransferase

Reaction: S-adenosyl-L-methionine + guanine2069 in 23S rRNA = S-adenosyl-L-homocysteine + N7-methylguanine2069 in 23S rRNA

Other name(s): rlmK (gene name); 23S rRNA m7G2069 methyltransferase

Systematic name: S-adenosyl-L-methionine:23S rRNA (guanine2069-N7)-methyltransferase

Comments: The enzyme specifically methylates guanine2069 at position N7 in 23S rRNA. In γ-proteobacteria the enzyme also catalyses EC 2.1.1.173, 23S rRNA (guanine2445-N2)-methyltransferase, while in β-proteobacteria the activities are carried out by separate proteins [1]. The enzyme from the γ-proteobacterium Escherichia coli has RNA unwinding activity as well [1].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Kimura, S., Ikeuchi, Y., Kitahara, K., Sakaguchi, Y., Suzuki, T. and Suzuki, T. Base methylations in the double-stranded RNA by a fused methyltransferase bearing unwinding activity. Nucleic Acids Res. 40 (2012) 4071-4085. [PMID: 22210896]

[EC 2.1.1.264 created 2012]

EC 2.1.1.265

Accepted name: tellurite methyltransferase

Reaction: S-adenosyl-L-methionine + tellurite = S-adenosyl-L-homocysteine + methanetelluronate

Other name(s): TehB

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

Comments: The enzyme is involved in the detoxification of tellurite. It can also methylate selenite and selenium dioxide.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Liu, M., Turner, R.J., Winstone, T.L., Saetre, A., Dyllick-Brenzinger, M., Jickling, G., Tari, L.W., Weiner, J.H. and Taylor, D.E. Escherichia coli TehB requires S-adenosylmethionine as a cofactor to mediate tellurite resistance. J. Bacteriol. 182 (2000) 6509-6513. [PMID: 11053398]

2. Choudhury, H.G., Cameron, A.D., Iwata, S. and Beis, K. Structure and mechanism of the chalcogen-detoxifying protein TehB from Escherichia coli. Biochem. J. 435 (2011) 85-91. [PMID: 21244361]

[EC 2.1.1.265 created 2012]

EC 2.1.1.266

Accepted name: 23S rRNA (adenine2030-N6)-methyltransferase

Reaction: S-adenosyl-L-methionine + adenine2030 in 23S rRNA = S-adenosyl-L-homocysteine + N6-methyladenine2030 in 23S rRNA

Other name(s): YhiR protein; rlmJ (gene name); m6A2030 methyltransferase

Systematic name: S-adenosyl-L-methionine:23S rRNA (adenine2030-N6)-methyltransferase

Comments: The recombinant RlmJ protein is most active in methylating deproteinized 23S ribosomal subunit, and does not methylate the completely assembled 50S subunits [1].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Golovina, A.Y., Dzama, M.M., Osterman, I.A., Sergiev, P.V., Serebryakova, M.V., Bogdanov, A.A. and Dontsova, O.A. The last rRNA methyltransferase of E. coli revealed: the yhiR gene encodes adenine-N6 methyltransferase specific for modification of A2030 of 23S ribosomal RNA. RNA 18 (2012) 1725-1734. [PMID: 22847818]

[EC 2.1.1.266 created 2013]

EC 2.1.1.267

Accepted name: flavonoid 3',5'-methyltransferase

Reaction: (1) S-adenosyl-L-methionine + a 3'-hydroxyflavonoid = S-adenosyl-L-homocysteine + a 3'-methoxyflavonoid
(2) S-adenosyl-L-methionine + a 5'-hydroxy-3'-methoxyflavonoid = S-adenosyl-L-homocysteine + a 3',5'-dimethoxyflavonoid

For diagram of reaction click here.

Glossary: delphinidin = 3,3',4',5,5',7-hexahydroxyflavylium
cyanidin = 3,3',4',5,7-pentahydroxyflavylium
myricetin = 3,3',4',5,5',7-hexahydroxyflavone
quercetin = 3,3',4',5,7-pentahydroxyflavone

Other name(s): AOMT; CrOMT2

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

Comments: Isolated from Vitis vinifera (grape) [2]. Most active with delphinidin 3-glucoside but also acts on cyanidin 3-glucoside, cyanidin, myricetin, quercetin and quercetin 3-glucoside. The enzyme from Catharanthus roseus was most active with myricetin [1].

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:

References:

1. Cacace, S., Schröder, G., Wehinger, E., Strack, D., Schmidt, J. and Schröder, J. A flavonol O-methyltransferase from Catharanthus roseus performing two sequential methylations. Phytochemistry 62 (2003) 127-137. [PMID: 12482447]

2. Hugueney, P., Provenzano, S., Verries, C., Ferrandino, A., Meudec, E., Batelli, G., Merdinoglu, D., Cheynier, V., Schubert, A. and Ageorges, A. A novel cation-dependent O-methyltransferase involved in anthocyanin methylation in grapevine. Plant Physiol. 150 (2009) 2057-2070. [PMID: 19525322]

[EC 2.1.1.267 created 2013, modified 2014]

EC 2.1.1.268

Accepted name: tRNAThr (cytosine32-N3)-methyltransferase

Reaction: (1) S-adenosyl-L-methionine + cytosine32 in tRNAThr = S-adenosyl-L-homocysteine + N3-methylcytosine32 in tRNAThr
(2) S-adenosyl-L-methionine + cytosine32 in tRNASer = S-adenosyl-L-homocysteine + N3-methylcytosine32 in tRNASer

Other name(s): ABP140; Trm140p

Systematic name: S-adenosyl-L-methionine:tRNAThr (cytosine32-N3)-methyltransferase

Comments: The enzyme from Saccharomyces cerevisiae specifically methylates cytosine32 in tRNAThr and in tRNASer.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Noma, A., Yi, S., Katoh, T., Takai, Y., Suzuki, T. and Suzuki, T. Actin-binding protein ABP140 is a methyltransferase for 3-methylcytidine at position 32 of tRNAs in Saccharomyces cerevisiae. RNA 17 (2011) 1111-1119. [PMID: 21518805]

2. D'Silva, S., Haider, S.J. and Phizicky, E.M. A domain of the actin binding protein Abp140 is the yeast methyltransferase responsible for 3-methylcytidine modification in the tRNA anti-codon loop. RNA 17 (2011) 1100-1110. [PMID: 21518804]

[EC 2.1.1.268 created 2013]

EC 2.1.1.269

Accepted name: dimethylsulfoniopropionate demethylase

Reaction: S,S-dimethyl-β-propiothetin + tetrahydrofolate = 3-(methylsulfanyl)propanoate + 5-methyltetrahydrofolate

For diagram of reaction click here.

Glossary: S,S-dimethyl-β-propiothetin = 3-(S,S-dimethylsulfonio)propanoate

Other name(s): dmdA (gene name); dimethylsulfoniopropionate-dependent demethylase A

Systematic name: S,S-dimethyl-β-propiothetin:tetrahydrofolate S-methyltransferase

Comments: The enzyme from the marine bacteria Pelagibacter ubique and Ruegeria pomeroyi are specific towards S,S-dimethyl-β-propiothetin. They do not demethylate glycine-betaine [1,2].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Jansen, M. and Hansen, T.A. Tetrahydrofolate serves as a methyl acceptor in the demethylation of dimethylsulfoniopropionate in cell extracts of sulfate-reducing bacteria. Arch. Microbiol. 169 (1998) 84-87. [PMID: 9396840]

2. Reisch, C.R., Moran, M.A. and Whitman, W.B. Dimethylsulfoniopropionate-dependent demethylase (DmdA) from Pelagibacter ubique and Silicibacter pomeroyi. J. Bacteriol. 190 (2008) 8018-8024. [PMID: 18849431]

3. Schuller, D.J., Reisch, C.R., Moran, M.A., Whitman, W.B. and Lanzilotta, W.N. Structures of dimethylsulfoniopropionate-dependent demethylase from the marine organism Pelagibacter ubique. Protein Sci. 21 (2012) 289-298. [PMID: 22162093]

[EC 2.1.1.269 created 2013]

EC 2.1.1.270

Accepted name: (+)-6a-hydroxymaackiain 3-O-methyltransferase

Reaction: S-adenosyl-L-methionine + (+)-6a-hydroxymaackiain = S-adenosyl-L-homocysteine + (+)-pisatin

Glossary: (+)-6a-hydroxymaackiain = (6aR,12aR)-6H-[1,3]dioxolo[5,6][1]benzofuro[3,2-c]chromene-3,6a(12aH)-diol
(+)-pisatin = (6aR,12aR)-3-methoxy-6H-[1,3]dioxolo[5,6][1]benzofuro[3,2-c]chromen-6a(12aH)-ol

Other name(s): HM3OMT; HMM2

Systematic name: S-adenosyl-L-methionine:(+)-6a-hydroxymaackiain 3-O-methyltransferase

Comments: The protein from the plant Pisum sativum (garden pea) methylates (+)-6a-hydroxymaackiain at the 3-position. It also methylates 2,7,4'-trihydroxyisoflavanone on the 4'-position (cf. EC 2.1.1.212, 2,7,4-trihydroxyisoflavanone 4-O-methyltransferase) with lower activity.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Preisig, C.L., Matthews, D.E. and Vanetten, H.D. Purification and characterization of S-adenosyl-L-methionine:6a-hydroxymaackiain 3-O-methyltransferase from Pisum sativum. Plant Physiol. 91 (1989) 559-566. [PMID: 16667069]

2. Wu, Q., Preisig, C.L. and VanEtten, H.D. Isolation of the cDNAs encoding (+)6a-hydroxymaackiain 3-O-methyltransferase, the terminal step for the synthesis of the phytoalexin pisatin in Pisum sativum. Plant Mol. Biol. 35 (1997) 551-560. [PMID: 9349277]

3. Liu, C.J., Deavours, B.E., Richard, S.B., Ferrer, J.L., Blount, J.W., Huhman, D., Dixon, R.A. and Noel, J.P. Structural basis for dual functionality of isoflavonoid O-methyltransferases in the evolution of plant defense responses. Plant Cell 18 (2006) 3656-3669. [PMID: 17172354]

4. Akashi, T., VanEtten, H.D., Sawada, Y., Wasmann, C.C., Uchiyama, H. and Ayabe, S. Catalytic specificity of pea O-methyltransferases suggests gene duplication for (+)-pisatin biosynthesis. Phytochemistry 67 (2006) 2525-2530. [PMID: 17067644]

[EC 2.1.1.270 created 2013]

EC 2.1.1.271

Accepted name: cobalt-precorrin-4 methyltransferase

Reaction: S-adenosyl-L-methionine + cobalt-precorrin-4 = S-adenosyl-L-homocysteine + cobalt-precorrin-5A

For diagram of reaction click here.

Other name(s): CbiF

Systematic name: S-adenosyl-L-methionine:cobalt-precorrin-4 11-methyltransferase

Comments: This enzyme, which participates in the anaerobic (early cobalt insertion) cobalamin biosynthesis pathway, catalyses the methylation of C-11 in cobalt-precorrin-4 to form cobalt-precorrin-5A. See EC 2.1.1.133, precorrin-4 C11-methyltransferase, for the equivalent enzyme that participates in the aerobic cobalamin biosynthesis pathway.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Raux, E., Schubert, H.L., Woodcock, S.C., Wilson, K.S. and Warren, M.J. Cobalamin (vitamin B12) biosynthesis--cloning, expression and crystallisation of the Bacillus megaterium S-adenosyl-L-methionine-dependent cobalt-precorrin-4 transmethylase CbiF. Eur. J. Biochem. 254 (1998) 341-346. [PMID: 9660189]

2. Schubert, H.L., Wilson, K.S., Raux, E., Woodcock, S.C. and Warren, M.J. The X-ray structure of a cobalamin biosynthetic enzyme, cobalt-precorrin-4 methyltransferase. Nat. Struct. Biol. 5 (1998) 585-592. [PMID: 9665173]

3. Kajiwara, Y., Santander, P.J., Roessner, C.A., Perez, L.M. and Scott, A.I. Genetically engineered synthesis and structural characterization of cobalt-precorrin 5A and -5B, two new intermediates on the anaerobic pathway to vitamin B12: definition of the roles of the CbiF and CbiG enzymes. J. Am. Chem. Soc. 128 (2006) 9971-9978. [PMID: 16866557]

[EC 2.1.1.271 created 2013]

EC 2.1.1.272

Accepted name: cobalt-factor III methyltransferase

Reaction: S-adenosyl-L-methionine + cobalt-factor III + reduced acceptor = S-adenosyl-L-homocysteine + cobalt-precorrin-4 + acceptor

For diagram of reaction click here.

Other name(s): CbiH60 (gene name)

Systematic name: S-adenosyl-L-methionine:cobalt-factor III 17-methyltransferase (ring contracting)

Comments: Isolated from the bacterium Bacillus megaterium. The enzyme, which participates in the anaerobic (early cobalt insertion) pathway of adenosylcobalamin biosynthesis, catalyses a crucial reaction where the tetrapyrrole ring contracts as a result of methylation of C-17. Contains a [4Fe-4S] cluster. It can also convert cobalt-precorrin-3 to cobalt-precorrin-4. The reductant may be thioredoxin. See EC 2.1.1.131, precorrin-3B C17-methyltransferase, for the corresponding enzyme that participates in the aerobic cobalamin biosynthesis pathway.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Moore, S.J., Biedendieck, R., Lawrence, A.D., Deery, E., Howard, M.J., Rigby, S.E. and Warren, M.J. Characterization of the enzyme CbiH60 involved in anaerobic ring contraction of the cobalamin (vitamin B12) biosynthetic pathway. J. Biol. Chem. 288 (2013) 297-305. [PMID: 23155054]

[EC 2.1.1.272 created 2013]

EC 2.1.1.273

Accepted name: benzoate O-methyltransferase

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

Other name(s): BAMT; S-adenosyl-L-methionine:benzoic acid carboxyl methyltransferase

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

Comments: While the enzyme from the plant Zea mays is specific for benzoate [6], the enzymes from Arabidopsis species and Clarkia breweri also catalyse the reaction of EC 2.1.1.274, salicylate 1-O-methyltransferase [1,5]. In snapdragon (Antirrhinum majus) two isoforms are found, one specific for benzoate [2,3] and one that is also active towards salicylate [4]. The volatile product is an important scent compound in some flowering species [2].

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, CAS registry number:

References:

1. Ross, J.R., Nam, K.H., D'Auria, J.C. and Pichersky, E. S-adenosyl-L-methionine:salicylic acid carboxyl methyltransferase, an enzyme involved in floral scent production and plant defense, represents a new class of plant methyltransferases. Arch. Biochem. Biophys. 367 (1999) 9-16. [PMID: 10375393]

2. Dudareva, N., Murfitt, L.M., Mann, C.J., Gorenstein, N., Kolosova, N., Kish, C.M., Bonham, C. and Wood, K. Developmental regulation of methyl benzoate biosynthesis and emission in snapdragon flowers. Plant Cell 12 (2000) 949-961. [PMID: 10852939]

3. Murfitt, L.M., Kolosova, N., Mann, C.J. and Dudareva, N. Purification and characterization of S-adenosyl-L-methionine:benzoic acid carboxyl methyltransferase, the enzyme responsible for biosynthesis of the volatile ester methyl benzoate in flowers of Antirrhinum majus. Arch. Biochem. Biophys. 382 (2000) 145-151. [PMID: 11051108]

4. Negre, F., Kolosova, N., Knoll, J., Kish, C.M. and Dudareva, N. Novel S-adenosyl-L-methionine:salicylic acid carboxyl methyltransferase, an enzyme responsible for biosynthesis of methyl salicylate and methyl benzoate, is not involved in floral scent production in snapdragon flowers. Arch. Biochem. Biophys. 406 (2002) 261-270. [PMID: 12361714]

5. Chen, F., D'Auria, J.C., Tholl, D., Ross, J.R., Gershenzon, J., Noel, J.P. and Pichersky, E. An Arabidopsis thaliana gene for methylsalicylate biosynthesis, identified by a biochemical genomics approach, has a role in defense. Plant J. 36 (2003) 577-588. [PMID: 14617060]

6. Köllner, T.G., Lenk, C., Zhao, N., Seidl-Adams, I., Gershenzon, J., Chen, F. and Degenhardt, J. Herbivore-induced SABATH methyltransferases of maize that methylate anthranilic acid using s-adenosyl-L-methionine. Plant Physiol. 153 (2010) 1795-1807. [PMID: 20519632]

[EC 2.1.1.273 created 2013]

EC 2.1.1.274

Accepted name: salicylate 1-O-methyltransferase

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

Glossary: methyl salicylate = methyl 2-hydroxybenzoate

Other name(s): SAMT; S-adenosyl-L-methionine:salicylic acid carboxyl methyltransferase; salicylate carboxymethyltransferase

Systematic name: S-adenosyl-L-methionine:salicylate 1-O-methyltransferase

Comments: The enzyme, which is found in flowering plants, also has the activity of EC 2.1.1.273, benzoate O-methyltransferase.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, PDB, CAS registry number:

References:

1. Ross, J.R., Nam, K.H., D'Auria, J.C. and Pichersky, E. S-Adenosyl-L-methionine:salicylic acid carboxyl methyltransferase, an enzyme involved in floral scent production and plant defense, represents a new class of plant methyltransferases. Arch. Biochem. Biophys. 367 (1999) 9-16. [PMID: 10375393]

2. Negre, F., Kolosova, N., Knoll, J., Kish, C.M. and Dudareva, N. Novel S-adenosyl-L-methionine:salicylic acid carboxyl methyltransferase, an enzyme responsible for biosynthesis of methyl salicylate and methyl benzoate, is not involved in floral scent production in snapdragon flowers. Arch. Biochem. Biophys. 406 (2002) 261-270. [PMID: 12361714]

3. Chen, F., D'Auria, J.C., Tholl, D., Ross, J.R., Gershenzon, J., Noel, J.P. and Pichersky, E. An Arabidopsis thaliana gene for methylsalicylate biosynthesis, identified by a biochemical genomics approach, has a role in defense. Plant J. 36 (2003) 577-588. [PMID: 14617060]

4. Zubieta, C., Ross, J.R., Koscheski, P., Yang, Y., Pichersky, E. and Noel, J.P. Structural basis for substrate recognition in the salicylic acid carboxyl methyltransferase family. Plant Cell 15 (2003) 1704-1716. [PMID: 12897246]

[EC 2.1.1.274 created 2013]

EC 2.1.1.275

Accepted name: gibberellin A9 O-methyltransferase

Reaction: S-adenosyl-L-methionine + gibberellin A9 = S-adenosyl-L-homocysteine + methyl gibberellin A9

Glossary: gibberellin A9 = (1R,4aR,4bR,7R,9aR,10S,10aR)-1-methyl-8-methylene-13-oxododecahydro-4a,1-(epoxymethano)-7,9a-methanobenzo[a]azulene-10-carboxylic acid
methyl gibberellin A9 = methyl (1R,4aR,4bR,7R,9aR,10S,10aR)-1-methyl-8-methylene-13-oxododecahydro-4a,1-(epoxymethano)-7,9a-methanobenzo[a]azulene-10-carboxylate

Other name(s): GAMT1

Systematic name: S-adenosyl-L-methionine:gibberellin A9 O-methyltransferase

Comments: The enzyme also methylates gibberellins A20 (95%), A3 (80%), A4 (69%) and A34 (46%) with significant activity.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, CAS registry number:

References:

1. Varbanova, M., Yamaguchi, S., Yang, Y., McKelvey, K., Hanada, A., Borochov, R., Yu, F., Jikumaru, Y., Ross, J., Cortes, D., Ma, C.J., Noel, J.P., Mander, L., Shulaev, V., Kamiya, Y., Rodermel, S., Weiss, D. and Pichersky, E. Methylation of gibberellins by Arabidopsis GAMT1 and GAMT2. Plant Cell 19 (2007) 32-45. [PMID: 17220201]

[EC 2.1.1.275 created 2013]

EC 2.1.1.276

Accepted name: gibberellin A4 carboxyl methyltransferase

Reaction: S-adenosyl-L-methionine + gibberellin A4 = S-adenosyl-L-homocysteine + methyl gibberellin A4

Glossary: gibberellin A4 = (1S,2S,4aR,4bR,7R,9aR,10S,10aR)-2-hydroxy-1-methyl-8-methylidene-13-oxododecahydro-4a,1-(epoxymethano)-7,9a-methanobenzo[a]azulene-10-carboxylic acid
methyl gibberellin A4 = methyl (1S,2S,4aR,4bR,7R,9aR,10S,10aR)-2-hydroxy-1-methyl-8-methylene-13-oxododecahydro-4a,1-(epoxymethano)-7,9a-methanobenzo[a]azulene-10-carboxylate

Other name(s): GAMT2; gibberellin A4 O-methyltransferase

Systematic name: S-adenosyl-L-methionine:gibberellin A4 O-methyltransferase

Comments: The enzyme also methylates gibberellins A34 (80%), A9 (60%), and A3 (45%) with significant activity.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, CAS registry number:

References:

1. Varbanova, M., Yamaguchi, S., Yang, Y., McKelvey, K., Hanada, A., Borochov, R., Yu, F., Jikumaru, Y., Ross, J., Cortes, D., Ma, C.J., Noel, J.P., Mander, L., Shulaev, V., Kamiya, Y., Rodermel, S., Weiss, D. and Pichersky, E. Methylation of gibberellins by Arabidopsis GAMT1 and GAMT2. Plant Cell 19 (2007) 32-45. [PMID: 17220201]

[EC 2.1.1.276 created 2013]

EC 2.1.1.277

Accepted name: anthranilate O-methyltransferase

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

Other name(s): AAMT

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

Comments: In the plant maize (Zea mays), the isoforms AAMT1 and AAMT2 are specific for anthranilate while AAMT3 also has the activity of EC 2.1.1.273, benzoate methyltransferase.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, CAS registry number:

References:

1. Köllner, T.G., Lenk, C., Zhao, N., Seidl-Adams, I., Gershenzon, J., Chen, F. and Degenhardt, J. Herbivore-induced SABATH methyltransferases of maize that methylate anthranilic acid using s-adenosyl-L-methionine. Plant Physiol. 153 (2010) 1795-1807. [PMID: 20519632]

[EC 2.1.1.277 created 2013]

EC 2.1.1.278

Accepted name: indole-3-acetate O-methyltransferase

Reaction: S-adenosyl-L-methionine + (indol-3-yl)acetate = S-adenosyl-L-homocysteine + methyl (indol-3-yl)acetate

Other name(s): IAA carboxylmethyltransferase; IAMT

Systematic name: S-adenosyl-L-methionine:(indol-3-yl)acetate O-methyltransferase

Comments: Binds Mg2+. The enzyme is found in plants and is important for regulation of the plant hormone (indol-3-yl)acetate. The product, methyl (indol-3-yl)acetate is inactive as hormone [2].

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, PDB, CAS registry number:

References:

1. Zubieta, C., Ross, J.R., Koscheski, P., Yang, Y., Pichersky, E. and Noel, J.P. Structural basis for substrate recognition in the salicylic acid carboxyl methyltransferase family. Plant Cell 15 (2003) 1704-1716. [PMID: 12897246]

2. Li, L., Hou, X., Tsuge, T., Ding, M., Aoyama, T., Oka, A., Gu, H., Zhao, Y. and Qu, L.J. The possible action mechanisms of indole-3-acetic acid methyl ester in Arabidopsis. Plant Cell Rep. 27 (2008) 575-584. [PMID: 17926040]

3. Zhao, N., Ferrer, J.L., Ross, J., Guan, J., Yang, Y., Pichersky, E., Noel, J.P. and Chen, F. Structural, biochemical, and phylogenetic analyses suggest that indole-3-acetic acid methyltransferase is an evolutionarily ancient member of the SABATH family. Plant Physiol. 146 (2008) 455-467. [PMID: 18162595]

[EC 2.1.1.278 created 2013]

EC 2.1.1.279

Accepted name: trans-anol O-methyltransferase

Reaction: (1) S-adenosyl-L-methionine + trans-anol = S-adenosyl-L-homocysteine + trans-anethole
(2) S-adenosyl-L-methionine + isoeugenol = S-adenosyl-L-homocysteine + isomethyleugenol

Glossary: trans-anol = 4-[(1E)-prop-1-en-1-yl]phenol
trans-anethole = 1-methoxy-4-[(1E)-prop-1-en-1-yl]benzene

Other name(s): AIMT1; S-adenosyl-L-methionine:t-anol/isoeugenol O-methyltransferase; t-anol O-methyltransferase

Systematic name: S-adenosyl-L-methionine:trans-anol O-methyltransferase

Comments: The enzyme from anise (Pimpinella anisum) is highly specific for substrates in which the double bond in the propenyl side chain is located between C7 and C8, and, in contrast to EC 2.1.1.146, (iso)eugenol O-methyltransferase, does not have activity with eugenol or chavicol.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, CAS registry number:

References:

1. Koeduka, T., Baiga, T.J., Noel, J.P. and Pichersky, E. Biosynthesis of t-anethole in anise: characterization of t-anol/isoeugenol synthase and an O-methyltransferase specific for a C7-C8 propenyl side chain. Plant Physiol. 149 (2009) 384-394. [PMID: 18987218]

[EC 2.1.1.279 created 2013]

EC 2.1.1.280

Accepted name: selenocysteine Se-methyltransferase

Reaction: S-methyl-L-methionine + L-selenocysteine = L-methionine + Se-methyl-L-selenocysteine

Other name(s): SMT

Systematic name: S-methyl-L-methionine:L-selenocysteine Se-methyltransferase

Comments: The enzyme uses S-adenosyl-L-methionine as methyl donor less actively than S-methyl-L-methionine. The enzyme from broccoli (Brassica oleracea var. italica) also has the activity of EC 2.1.1.10, homocysteine S-methyltransferase [4].

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, CAS registry number:

References:

1. Neuhierl, B. and Bock, A. On the mechanism of selenium tolerance in selenium-accumulating plants. Purification and characterization of a specific selenocysteine methyltransferase from cultured cells of Astragalus bisculatus. Eur. J. Biochem. 239 (1996) 235-238. [PMID: 8706715]

2. Neuhierl, B., Thanbichler, M., Lottspeich, F. and Bock, A. A family of S-methylmethionine-dependent thiol/selenol methyltransferases. Role in selenium tolerance and evolutionary relation. J. Biol. Chem. 274 (1999) 5407-5414. [PMID: 10026151]

3. Lyi, S.M., Heller, L.I., Rutzke, M., Welch, R.M., Kochian, L.V. and Li, L. Molecular and biochemical characterization of the selenocysteine Se-methyltransferase gene and Se-methylselenocysteine synthesis in broccoli. Plant Physiol. 138 (2005) 409-420. [PMID: 15863700]

4. Lyi, S.M., Zhou, X., Kochian, L.V. and Li, L. Biochemical and molecular characterization of the homocysteine S-methyltransferase from broccoli (Brassica oleracea var. italica). Phytochemistry 68 (2007) 1112-1119. [PMID: 17391716]

[EC 2.1.1.280 created 2013]

EC 2.1.1.281

Accepted name: phenylpyruvate C3-methyltransferase

Reaction: S-adenosyl-L-methionine + 3-phenylpyruvate = S-adenosyl-L-homocysteine + (3S)-2-oxo-3-phenylbutanoate

Glossary: 3-phenylpyruvate = 2-oxo-3-phenylpropanoate
(3S)-2-oxo-3-methyl-3-phenylpropanoate = (3S)-β-methyl-phenylpyruvate

Other name(s): phenylpyruvate Cβ-methyltransferase; phenylpyruvate methyltransferase; mppJ (gene name)

Systematic name: S-adenosyl-L-methionine:2-oxo-3-phenylpropanoate C3-methyltransferase

Comments: The enzyme from the bacterium Streptomyces hygroscopicus NRRL3085 is involved in synthesis of the nonproteinogenic amino acid (2S,3S)-β-methyl-phenylalanine, a building block of the antibiotic mannopeptimycin.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, PDB, CAS registry number:

References:

1. Huang, Y.T., Lyu, S.Y., Chuang, P.H., Hsu, N.S., Li, Y.S., Chan, H.C., Huang, C.J., Liu, Y.C., Wu, C.J., Yang, W.B. and Li, T.L. In vitro characterization of enzymes involved in the synthesis of nonproteinogenic residue (2S,3S)-β-methylphenylalanine in glycopeptide antibiotic mannopeptimycin. Chembiochem 10 (2009) 2480-2487. [PMID: 19731276]

[EC 2.1.1.281 created 2013]

EC 2.1.1.282

Accepted name: tRNAPhe 7-[(3-amino-3-carboxypropyl)-4-demethylwyosine37-N4]-methyltransferase

Reaction: S-adenosyl-L-methionine + 7-[(3S)-(3-amino-3-carboxypropyl)]-4-demethylwyosine37 in tRNAPhe = S-adenosyl-L-homocysteine + 7-[(3S)-(3-amino-3-carboxypropyl)]wyosine37 in tRNAPhe

For diagram of reaction click here.

Glossary: wyosine = 4,6-dimethyl-3-(β-D-ribofuranosyl)-3,4-dihydro-9H-imidazo[1,2-a]purin-9-one
wybutosine = yW = 7-{(3S)-4-methoxy-3-[(methoxycarbonyl)amino]-4-oxobutyl}-4,5-dimethyl-3-(β-D-ribofuranosyl)-3,4-dihydro-9H-imidazo[1,2-a]purin-9-one

Other name(s): TYW3 (gene name); tRNA-yW synthesizing enzyme-3

Systematic name: S-adenosyl-L-methionine:tRNAPhe 7-[(3S)-(3-amino-3-carboxypropyl)-4-demethylwyosine-N4]-methyltransferase

Comments: The enzyme is involved in the biosynthesis of hypermodified tricyclic bases found at position 37 of certain tRNAs. These modifications are important for translational reading-frame maintenance. The enzyme is found in all eukaryotes and in some archaea, but not in bacteria. The eukaryotic enzyme is involved in the biosynthesis of wybutosine.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:

References:

1. Noma, A., Kirino, Y., Ikeuchi, Y. and Suzuki, T. Biosynthesis of wybutosine, a hyper-modified nucleoside in eukaryotic phenylalanine tRNA. EMBO J. 25 (2006) 2142-2154. [PMID: 16642040]

[EC 2.1.1.282 created 2013, modified 2014]

EC 2.1.1.283

Accepted name: emodin O-methyltransferase

Reaction: S-adenosyl-L-methionine + emodin = S-adenosyl-L-homocysteine + questin

Glossary: emodin = 1,3,8-trihydroxy-6-methyl-9,10-anthraquinone
questin = 1,6-dihydroxy-8-methoxy-3-methyl-9,10-anthraquinone

Other name(s): EOMT

Systematic name: S-adenosyl-L-methionine:emodin 8-O-methyltransferase

Comments: The enzyme is involved in biosynthesis of the seco-anthraquinone (+)-geodin.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, CAS registry number:

References:

1. Chen, Z.G., Fujii, I., Ebizuka, Y. and Sankawa, U. Emodin O-methyltransferase from Aspergillus terreus. Arch. Microbiol. 158 (1992) 29-34. [PMID: 1444712]

[EC 2.1.1.283 created 2013]

EC 2.1.1.284

Accepted name: 8-demethylnovobiocic acid C8-methyltransferase

Reaction: S-adenosyl-L-methionine + 8-demethylnovobiocic acid = S-adenosyl-L-homocysteine + novobiocic acid

For diagram of reaction click here.

Glossary: novobiocic acid = N-(2,7-dihydroxy-8-methyl-4-oxochromen-3-yl)-4-hydroxy-3-(3-methylbut-2-enyl) benzamide

Other name(s): NovO

Systematic name: S-adenosyl-L-methionine:8-demethylnovobiocic acid C8-methyltransferase

Comments: The enzyme is involved in the biosynthesis of the aminocoumarin antibiotic novobiocin.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, PDB, CAS registry number:

References:

1. Pacholec, M., Tao, J. and Walsh, C.T. CouO and NovO: C-methyltransferases for tailoring the aminocoumarin scaffold in coumermycin and novobiocin antibiotic biosynthesis. Biochemistry 44 (2005) 14969-14976. [PMID: 16274243]

[EC 2.1.1.284 created 2013]

EC 2.1.1.285

Accepted name: demethyldecarbamoylnovobiocin O-methyltransferase

Reaction: S-adenosyl-L-methionine + demethyldecarbamoylnovobiocin = S-adenosyl-L-homocysteine + decarbamoylnovobiocin

For diagram of reaction click here.

Glossary: demethyldecarbamoylnovobiocin = N-{7-[(6-deoxy-5-methyl-β-D-gulopyranosyl)oxy]-4-hydroxy-8-methyl-2-oxo-2H-chromen-3-yl}-4-hydroxy-3-(3-methylbut-2-en-1-yl)benzamide
decarbamoylnovobiocin = N-{7-[(6-deoxy-5-methyl-4-O-methyl-β-D-gulopyranosyl)oxy]4-hydroxy-8-methyl-2-oxo-2H-chromen-3-yl}-4-hydroxy-3-(3-methyl-2-buten-1-yl)benzamide

Other name(s): NovP

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

Comments: The enzyme is involved in the biosynthesis of the aminocoumarin antibiotic novobiocin.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, PDB, CAS registry number:

References:

1. Freel Meyers, C.L., Oberthur, M., Xu, H., Heide, L., Kahne, D. and Walsh, C.T. Characterization of NovP and NovN: completion of novobiocin biosynthesis by sequential tailoring of the noviosyl ring. Angew. Chem. Int. Ed. Engl. 43 (2004) 67-70. [PMID: 14694473]

2. Gomez Garcia, I., Stevenson, C.E., Uson, I., Freel Meyers, C.L., Walsh, C.T. and Lawson, D.M. The crystal structure of the novobiocin biosynthetic enzyme NovP: the first representative structure for the TylF O-methyltransferase superfamily. J. Mol. Biol. 395 (2010) 390-407. [PMID: 19857499]

[EC 2.1.1.285 created 2013]

EC 2.1.1.286

Accepted name: 25S rRNA (adenine2142-N1)-methyltransferase

Reaction: S-adenosyl-L-methionine + adenine2142 in 25S rRNA = S-adenosyl-L-homocysteine + N1-methyladenine2142 in 25S rRNA

Other name(s): BMT2 (gene name); 25S rRNA m1A2142 methyltransferase

Systematic name: S-adenosyl-L-methionine:25S rRNA (adenine2142-N1)-methyltransferase

Comments: In the yeast Saccharomyces cerevisiae this methylation is important for resistance towards hydrogen peroxide and the antibiotic anisomycin.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, CAS registry number:

References:

1. Sharma, S., Watzinger, P., Kotter, P. and Entian, K.D. Identification of a novel methyltransferase, Bmt2, responsible for the N-1-methyl-adenosine base modification of 25S rRNA in Saccharomyces cerevisiae. Nucleic Acids Res. 41 (2013) 5428-5443. [PMID: 23558746]

[EC 2.1.1.286 created 2013]

EC 2.1.1.287

Accepted name: 25S rRNA (adenine645-N1)-methyltransferase

Reaction: S-adenosyl-L-methionine + adenine645 in 25S rRNA = S-adenosyl-L-homocysteine + N1-methyladenine645 in 25S rRNA

Other name(s): 25S rRNA m1A645 methyltransferase; Rrp8

Systematic name: S-adenosyl-L-methionine:25S rRNA (adenine645-N1)-methyltransferase

Comments: The enzyme is found in eukaryotes. The adenine position refers to tRNA the yeast Saccharomyces cerevisiae, in which the enzyme is important for ribosome biogenesis.

Links to other databases: BRENDA, EXPASY, KEGG Metacyc, CAS registry number:

References:

1. Peifer, C., Sharma, S., Watzinger, P., Lamberth, S., Kotter, P. and Entian, K.D. Yeast Rrp8p, a novel methyltransferase responsible for m1A 645 base modification of 25S rRNA. Nucleic Acids Res. 41 (2013) 1151-1163. [PMID: 23180764]

[EC 2.1.1.287 created 2013]

EC 2.1.1.288

Accepted name: aklanonic acid methyltransferase

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

For diagram of reaction click here.

Glossary: methyl aklanonate = methyl [1,4,5-trihydroxy-9,10-dioxo-3-(3-oxopentanoyl)-9,10-dihydroanthracen-2-yl]acetate
aklanonate = [4,5-dihydroxy-9,10-dioxo-3-(3-oxopentanoyl)-9,10-dihydroanthracen-2-yl]acetic acid

Other name(s): DauC; AAMT

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

Comments: The enzyme from the Gram-positive bacterium Streptomyces sp. C5 is involved in the biosynthesis of the anthracycline daunorubicin.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Dickens, M.L., Ye, J. and Strohl, W.R. Analysis of clustered genes encoding both early and late steps in daunomycin biosynthesis by Streptomyces sp. strain C5. J. Bacteriol. 177 (1995) 536-543. [PMID: 7836284]

[EC 2.1.1.288 created 2013]

EC 2.1.1.289

Accepted name: cobalt-precorrin-7 (C5)-methyltransferase

Reaction: S-adenosyl-L-methionine + cobalt-precorrin-7 = S-adenosyl-L-homocysteine + cobalt-precorrin-8

For diagram of reaction, click here

Other name(s): CbiE

Systematic name: S-adenosyl-L-methionine:precorrin-7 C5-methyltransferase

Comments: This enzyme catalyses the methylation at C-5 of cobalt-precorrin-7, a step in the anaerobic (early cobalt insertion) adenosylcobalamin biosynthesis pathway. The equivalent activity in the aerobic adenosylcobalamin biosynthesis pathway is catalysed by the bifunctional enzyme EC 2.1.1.132, precorrin-6B C5.15-methyltransferase (decarboxylating).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Santander, P.J., Kajiwara, Y., Williams, H.J. and Scott, A.I. Structural characterization of novel cobalt corrinoids synthesized by enzymes of the vitamin B12 anaerobic pathway. Bioorg. Med. Chem. 14 (2006) 724-731. [PMID: 16198574]

2. Moore, S.J., Lawrence, A.D., Biedendieck, R., Deery, E., Frank, S., Howard, M.J., Rigby, S.E. and Warren, M.J. Elucidation of the anaerobic pathway for the corrin component of cobalamin (vitamin B12). Proc. Natl. Acad. Sci. USA 110 (2013) 14906-14911. [PMID: 23922391]

[EC 2.1.1.289 created 2010]

EC 2.1.1.290

Accepted name: tRNAPhe [7-(3-amino-3-carboxypropyl)wyosine37-O]-methyltransferase

Reaction: S-adenosyl-L-methionine + 7-[(3S)-3-amino-3-carboxypropyl]wyosine37 in tRNAPhe = S-adenosyl-L-homocysteine + 7-[(3S)-3-amino-3-(methoxycarbonyl)propyl]wyosine37 in tRNAPhe

For diagram of reaction, click here

Glossary: wyosine = 4,6-dimethyl-3-(β-D-ribofuranosyl)-3,4-dihydro-9H-imidazo[1,2-a]purin-9-one
wybutosine = yW = 7-[(3S)-3-(methoxycarbonyl)-3-(methoxycarbonylamino)propyl]-4,5-dimethyl-3-(β-D-ribofuranosyl)-3,4-dihydro-9H-imidazo[1,2-a]purin-9-one

Other name(s): TYW4 (ambiguous); tRNA-yW synthesizing enzyme-4 (ambiguous)

Systematic name: S-adenosyl-L-methionine:tRNAPhe {7-[(3S)-3-amino-3-carboxypropyl]wyosine37-O}-methyltransferase

Comments: The enzyme is found only in eukaryotes, where it is involved in the biosynthesis of wybutosine, a hypermodified tricyclic base found at position 37 of certain tRNAs. The modification is important for translational reading-frame maintenance. In some species that produce hydroxywybutosine the enzyme uses 7-(2-hydroxy-3-amino-3-carboxypropyl)wyosine37 in tRNAPhe as substrate. The enzyme also has the activity of EC 2.3.1.231, tRNAPhe 7-[(3S)-4-methoxy-(3-amino-3-carboxypropyl)wyosine37-O]-carbonyltransferase [2].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Noma, A., Kirino, Y., Ikeuchi, Y. and Suzuki, T. Biosynthesis of wybutosine, a hyper-modified nucleoside in eukaryotic phenylalanine tRNA. EMBO J. 25 (2006) 2142-2154. [PMID: 16642040]

2. Suzuki, Y., Noma, A., Suzuki, T., Ishitani, R. and Nureki, O. Structural basis of tRNA modification with CO2 fixation and methylation by wybutosine synthesizing enzyme TYW4. Nucleic Acids Res. 37 (2009) 2910-2925. [PMID: 19287006]

3. Kato, M., Araiso, Y., Noma, A., Nagao, A., Suzuki, T., Ishitani, R. and Nureki, O. Crystal structure of a novel JmjC-domain-containing protein, TYW5, involved in tRNA modification. Nucleic Acids Res. 39 (2011) 1576-1585. [PMID: 20972222]

[EC 2.1.1.290 created 2013]

EC 2.1.1.291

Accepted name: (R,S)-reticuline 7-O-methyltransferase

Reaction: (1) S-adenosyl-L-methionine + (S)-reticuline = S-adenosyl-L-homocysteine + (S)-laudanine
(2) S-adenosyl-L-methionine + (R)-reticuline = S-adenosyl-L-homocysteine + (R)-laudanine

For diagram of reaction, click here

Glossary: (S)-reticuline = (1S)-1-[(3-hydroxy-4-methoxyphenyl)methyl]-6-methoxy-2-methyl-1,2,3,4-tetrahydroisoquinolin-7-ol
(R)-reticuline = (1R)-1-[(3-hydroxy-4-methoxyphenyl)methyl]-6-methoxy-2-methyl-1,2,3,4-tetrahydroisoquinolin-7-ol
(S)-laudanine = 5-[((1S)-6,7-dimethoxy-2-methyl-1,2,3,4-tetrahydroisoquinolin-1-yl)methyl]-2-methoxyphenol
(R)-laudanine = 5-[((1R)-6,7-dimethoxy-2-methyl-1,2,3,4-tetrahydroisoquinolin-1-yl)methyl]-2-methoxyphenol

Systematic name: S-adenosyl-L-methionine:(R,S)-reticuline 7-O-methyltransferase

Comments: The enzyme from the plant Papaver somniferum (opium poppy) methylates (S)- and (R)-reticuline with equal efficiency and is involved in the biosynthesis of tetrahydrobenzylisoquinoline alkaloids.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Ounaroon, A., Decker, G., Schmidt, J., Lottspeich, F. and Kutchan, T.M. (R,S)-Reticuline 7-O-methyltransferase and (R,S)-norcoclaurine 6-O-methyltransferase of Papaver somniferum - cDNA cloning and characterization of methyl transfer enzymes of alkaloid biosynthesis in opium poppy. Plant J. 36 (2003) 808-819. [PMID: 14675446]

2. Weid, M., Ziegler, J. and Kutchan, T.M. The roles of latex and the vascular bundle in morphine biosynthesis in the opium poppy, Papaver somniferum. Proc. Natl. Acad. Sci. USA 101 (2004) 13957-13962. [PMID: 15353584]

[EC 2.1.1.291 created 2013]

EC 2.1.1.292

Accepted name: carminomycin 4-O-methyltransferase

Reaction: S-adenosyl-L-methionine + carminomycin = S-adenosyl-L-homocysteine + daunorubicin

For diagram of reaction, click here

Glossary: daunorubicin = (+)-daunomycin = (8S,10S)-8-acetyl-10-[(2S,4S,5S,6S)-4-amino-5-hydroxy-6-methyloxan-2-yl]oxy-6,8,11-trihydroxy-1-methoxy-9,10-dihydro-7H-tetracene-5,12-dione
carminomycin = (1S,3S)-3-acetyl-3,5,10,12-tetrahydroxy-6,11-dioxo-1,2,3,4,6,11-hexahydrotetracen-1-yl 3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranoside = (1S,3S)-3-acetyl-3,5,10,12-tetrahydroxy-6,11-dioxo-1,2,3,4,6,11-hexahydronaphthacen-1-yl 3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranoside
carubicin = (1S,3S)-3-acetyl-3,5,12-trihydroxy-10-methoxy-6,11-dioxo-1,2,3,4,6,11-hexahydrotetracen-1-yl 3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranoside
= (8S,10S)-8-acetyl-10-[(3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranosyl)oxy]-6,8,11-trihydroxy-1-methoxy-7,8,9,10-tetrahydronaphthacene-5,12-dione

Other name(s): DnrK; DauK

Systematic name: S-adenosyl-L-methionine:carminomycin 4-O-methyltransferase

Comments: The enzymes from the Gram-positive bacteria Streptomyces sp. C5 and Streptomyces peucetius are involved in the biosynthesis of the anthracycline daunorubicin. In vitro the enzyme from Streptomyces sp. C5 also catalyses the 4-O-methylation of 13-dihydrocarminomycin, rhodomycin D and 10-carboxy-13-deoxycarminomycin [3].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Connors, N.C. and Strohl, W.R. Partial purification and properties of carminomycin 4-O-methyltransferase from Streptomyces sp. strain C5. J. Gen. Microbiol. 139 Pt 6 (1993) 1353-1362. [PMID: 8360627]

2. Jansson, A., Koskiniemi, H., Mantsala, P., Niemi, J. and Schneider, G. Crystal structure of a ternary complex of DnrK, a methyltransferase in daunorubicin biosynthesis, with bound products. J. Biol. Chem. 279 (2004) 41149-41156. [PMID: 15273252]

3. Dickens, M.L., Priestley, N.D. and Strohl, W.R. In vivo and in vitro bioconversion of ε-rhodomycinone glycoside to doxorubicin: functions of DauP, DauK, and DoxA. J. Bacteriol. 179 (1997) 2641-2650. [PMID: 9098063]

[EC 2.1.1.292 created 2013]

EC 2.1.1.293

Accepted name: 6-hydroxytryprostatin B O-methyltransferase

Reaction: S-adenosyl-L-methionine + 6-hydroxytryprostatin B = S-adenosyl-L-homocysteine + tryprostatin A

For diagram of reaction, click here

Glossary: 6-hydroxytryprostatin B = (3S,8aS)-3-{[6-hydroxy-2-(3-methylbut-2-en-1-yl)-1H-indol-3-yl]methyl}hexahydropyrrolo[1,2-a]pyrazine-1,4-dione
tryprostatin A = (3S,8aS)-3-{[6-methoxy-2-(3-methylbut-2-en-1-yl)-1H-indol-3-yl]methyl}hexahydropyrrolo[1,2-a]pyrazine-1,4-dione

Other name(s): ftmD (gene name)

Systematic name: S-adenosyl-L-methionine:6-hydroxytryprostatin B O-methyltransferase

Comments: Involved in the biosynthetic pathways of several indole alkaloids such as tryprostatins, fumitremorgins and verruculogen.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Kato, N., Suzuki, H., Okumura, H., Takahashi, S. and Osada, H. A point mutation in ftmD blocks the fumitremorgin biosynthetic pathway in Aspergillus fumigatus strain Af293. Biosci. Biotechnol. Biochem. 77 (2013) 1061-1067. [PMID: 23649274]

[EC 2.1.1.293 created 2013]

EC 2.1.1.294

Accepted name: 3-O-phospho-polymannosyl GlcNAc-diphospho-ditrans,octacis-undecaprenol 3-phospho-methyltransferase

Reaction: S-adenosyl-L-methionine + 3-O-phospho-α-D-Man-(1→2)-α-D-Man-(1→2)-[α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-Man-(1→2)-α-D-Man-(1→2)]n-α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-GlcNAc-diphospho-ditrans,octacis-undecaprenol = S-adenosyl-L-homocysteine + 3-O-methylphospho-α-D-Man-(1→2)-α-D-Man-(1→2)-[α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-Man-(1→2)-α-D-Man-(1→2)]n-α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-GlcNAc-diphospho-ditrans,octacis-undecaprenol

Other name(s): WbdD; S-adenosyl-L-methionine:3-O-phospho-α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-α-D-Man-(1→3)]n-α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-GlcNAc-α-diphospho-ditrans,octacis-undecaprenol 3-phospho-methyltransferase

Systematic name: S-adenosyl-L-methionine:3-O-phospho-α-D-Man-(1→2)-α-D-Man-(1→2)-[α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-Man-(1→2)-α-D-Man-(1→2)]n-α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-GlcNAc-diphospho-ditrans,octacis-undecaprenol 3-phospho-methyltransferase

Comments: The enzyme is involved in the biosynthesis of the polymannose O-polysaccharide in the outer leaflet of the membrane of Escherichia coli serotype O9a. O-Polysaccharide structures vary extensively because of differences in the number and type of sugars in the repeat unit. The dual kinase/methylase WbdD also catalyses the preceding phosphorylation of α-D-Man-(1→2)-α-D-Man-(1→2)-[α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-Man-(1→2)-α-D-Man-(1→2)]n-α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-Man-(1→3)-α-D-GlcNAc-diphospho-ditrans,octacis-undecaprenol (cf. EC 2.7.1.181, polymannosyl GlcNAc-diphospho-ditrans,octacis-undecaprenol kinase).

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:

References:

1. Clarke, B.R., Cuthbertson, L. and Whitfield, C. Nonreducing terminal modifications determine the chain length of polymannose O antigens of Escherichia coli and couple chain termination to polymer export via an ATP-binding cassette transporter. J. Biol. Chem. 279 (2004) 35709-35718. [PMID: 15184370]

2. Clarke, B.R., Greenfield, L.K., Bouwman, C. and Whitfield, C. Coordination of polymerization, chain termination, and export in assembly of the Escherichia coli lipopolysaccharide O9a antigen in an ATP-binding cassette transporter-dependent pathway. J. Biol. Chem. 284 (2009) 30662-30672. [PMID: 19734145]

3. Clarke, B.R., Richards, M.R., Greenfield, L.K., Hou, D., Lowary, T.L. and Whitfield, C. In vitro reconstruction of the chain termination reaction in biosynthesis of the Escherichia coli O9a O-polysaccharide: the chain-length regulator, WbdD, catalyzes the addition of methyl phosphate to the non-reducing terminus of the growing glycan. J. Biol. Chem. 286 (2011) 41391-41401. [PMID: 21990359]

4. Liston, S.D., Clarke, B.R., Greenfield, L.K., Richards, M.R., Lowary, T.L. and Whitfield, C. Domain interactions control complex formation and polymerase specificity in the biosynthesis of the Escherichia coli O9a antigen. J. Biol. Chem. 290 (2015) 1075-1085. [PMID: 25422321]

[EC 2.1.1.294 created 2014, modified 2018]

EC 2.1.1.295

Accepted name: 2-methyl-6-phytyl-1,4-hydroquinone methyltransferase

Reaction: (1) S-adenosyl-L-methionine + 2-methyl-6-phytylbenzene-1,4-diol = S-adenosyl-L-homocysteine + 2,3-dimethyl-6-phytylbenzene-1,4-diol
(2) S-adenosyl-L-methionine + 2-methyl-6-all-trans-nonaprenylbenzene-1,4-diol = S-adenosyl-L-homocysteine + plastoquinol
(3) S-adenosyl-L-methionine + 6-geranylgeranyl-2-methylbenzene-1,4-diol = S-adenosyl-L-homocysteine + 6-geranylgeranyl-2,3-dimethylbenzene-1,4-diol

For diagram of reaction click here or click here or click here.

Other name(s): VTE3 (gene name); 2-methyl-6-solanyl-1,4-hydroquinone methyltransferase; MPBQ/MSBQ methyltransferase; MPBQ/MSBQ MT

Systematic name: S-adenosyl-L-methionine:2-methyl-6-phytyl-1,4-benzoquinol C3-methyltransferase

Comments: Involved in the biosynthesis of plastoquinol, as well as vitamin E (tocopherols and tocotrienols).

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:

References:

1. Shintani, D.K., Cheng, Z. and DellaPenna, D. The role of 2-methyl-6-phytylbenzoquinone methyltransferase in determining tocopherol composition in Synechocystis sp. PCC6803. FEBS Lett 511 (2002) 1-5. [PMID: 11821038]

2. Cheng, Z., Sattler, S., Maeda, H., Sakuragi, Y., Bryant, D.A. and DellaPenna, D. Highly divergent methyltransferases catalyze a conserved reaction in tocopherol and plastoquinone synthesis in cyanobacteria and photosynthetic eukaryotes. Plant Cell 15 (2003) 2343-2356. [PMID: 14508009]

3. Van Eenennaam, A.L., Lincoln, K., Durrett, T.P., Valentin, H.E., Shewmaker, C.K., Thorne, G.M., Jiang, J., Baszis, S.R., Levering, C.K., Aasen, E.D., Hao, M., Stein, J.C., Norris, S.R. and Last, R.L. Engineering vitamin E content: from Arabidopsis mutant to soy oil. Plant Cell 15 (2003) 3007-3019. [PMID: 14630966]

[EC 2.1.1.295 created 2014]

EC 2.1.1.296

Accepted name: methyltransferase cap2

Reaction: S-adenosyl-L-methionine + a 5'-(N7-methyl 5'-triphosphoguanosine)-(2'-O-methyl-ribonucleotide)-(ribonucleotide)-[mRNA] = S-adenosyl-L-homocysteine + a 5'-(N7-methyl 5'-triphosphoguanosine)-(2'-O-methyl-ribonucleotide)-(2'-O-methyl-ribonucleotide)-[mRNA]

Other name(s): CMTR2 (gene name); MTR2; cap2-MTase; mRNA (nucleoside-2'-O)-methyltransferase (ambiguous)

Systematic name: S-adenosyl-L-methionine:5'-(N7-methyl 5'-triphosphoguanosine)-(2'-O-methyl-ribonucleotide)-ribonucleotide-[mRNA] 2'-O-methyltransferase

Comments: The enzyme, found in higher eukaryotes including insects and vertebrates, and their viruses, methylates the ribose of the ribonucleotide at the second transcribed position of mRNAs and snRNAs. This methylation event is known as cap2. The human enzyme can also methylate mRNA molecules where the upstream ribonucleotide is not methylated (see EC 2.1.1.57, methyltransferase cap1), but with lower efficiency [2].

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:

References:

1. Arhin, G.K., Ullu, E. and Tschudi, C. 2'-O-methylation of position 2 of the trypanosome spliced leader cap 4 is mediated by a 48 kDa protein related to vaccinia virus VP39. Mol. Biochem. Parasitol. 147 (2006) 137-139. [PMID: 16516986]

2. Werner, M., Purta, E., Kaminska, K.H., Cymerman, I.A., Campbell, D.A., Mittra, B., Zamudio, J.R., Sturm, N.R., Jaworski, J. and Bujnicki, J.M. 2'-O-ribose methylation of cap2 in human: function and evolution in a horizontally mobile family. Nucleic Acids Res. 39 (2011) 4756-4768. [PMID: 21310715]

[EC 2.1.1.296 created 2014, modified 2021]

EC 2.1.1.297

Accepted name: peptide chain release factor N5-glutamine methyltransferase

Reaction: S-adenosyl-L-methionine + [peptide chain release factor 1 or 2]-L-glutamine = S-adenosyl-L-homocysteine + [peptide chain release factor 1 or 2]-N5-methyl-L-glutamine

Other name(s): N5-glutamine S-adenosyl-L-methionine dependent methyltransferase; N5-glutamine MTase; HemK; PrmC

Systematic name: S-adenosyl-L-methionine:[peptide chain release factor 1 or 2]-L-glutamine (N5-glutamine)-methyltransferase

Comments: Modifies the glutamine residue in the universally conserved glycylglycylglutamine (GGQ) motif of peptide chain release factor, resulting in almost complete loss of release activity.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:

References:

1. Nakahigashi, K., Kubo, N., Narita, S., Shimaoka, T., Goto, S., Oshima, T., Mori, H., Maeda, M., Wada, C. and Inokuchi, H. HemK, a class of protein methyl transferase with similarity to DNA methyl transferases, methylates polypeptide chain release factors, and hemK knockout induces defects in translational termination. Proc. Natl. Acad. Sci. USA 99 (2002) 1473-1478. [PMID: 11805295]

2. Heurgue-Hamard, V., Champ, S., Engstrom, A., Ehrenberg, M. and Buckingham, R.H. The hemK gene in Escherichia coli encodes the N5-glutamine methyltransferase that modifies peptide release factors. EMBO J. 21 (2002) 769-778. [PMID: 11847124]

3. Schubert, H.L., Phillips, J.D. and Hill, C.P. Structures along the catalytic pathway of PrmC/HemK, an N5-glutamine AdoMet-dependent methyltransferase. Biochemistry 42 (2003) 5592-5599. [PMID: 12741815]

4. Yoon, H.J., Kang, K.Y., Ahn, H.J., Shim, S.M., Ha, J.Y., Lee, S.K., Mikami, B. and Suh, S.W. X-ray crystallographic studies of HemK from Thermotoga maritima, an N5-glutamine methyltransferase. Mol. Cells 16 (2003) 266-269. [PMID: 14651272]

5. Yang, Z., Shipman, L., Zhang, M., Anton, B.P., Roberts, R.J. and Cheng, X. Structural characterization and comparative phylogenetic analysis of Escherichia coli HemK, a protein (N5)-glutamine methyltransferase. J. Mol. Biol. 340 (2004) 695-706. [PMID: 15223314]

6. Pannekoek, Y., Heurgue-Hamard, V., Langerak, A.A., Speijer, D., Buckingham, R.H. and van der Ende, A. The N5-glutamine S-adenosyl-L-methionine-dependent methyltransferase PrmC/HemK in Chlamydia trachomatis methylates class 1 release factors. J. Bacteriol. 187 (2005) 507-511. [PMID: 15629922]

[EC 2.1.1.297 created 2014]

EC 2.1.1.298

Accepted name: ribosomal protein uL3 N5-glutamine methyltransferase

Reaction: S-adenosyl-L-methionine + [ribosomal protein uL3]-L-glutamine = S-adenosyl-L-homocysteine + [ribosomal protein uL3]-N5-methyl-L-glutamine

Other name(s): YfcB; PrmB

Systematic name: S-adenosyl-L-methionine:[ribosomal protein uL3]-L-glutamine (N5-glutamine)-methyltransferase

Comments: Modifies the glutamine residue in the glycylglycylglutamine (GGQ) motif of ribosomal protein uL3 (Gln150 in the protein from the bacterium Escherichia coli). The enzyme does not act on peptide chain release factor 1 or 2.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:

References:

1. Heurgue-Hamard, V., Champ, S., Engstrom, A., Ehrenberg, M. and Buckingham, R.H. The hemK gene in Escherichia coli encodes the N5-glutamine methyltransferase that modifies peptide release factors. EMBO J. 21 (2002) 769-778. [PMID: 11847124]

[EC 2.1.1.298 created 2014, modified 2023]

EC 2.1.1.299

Accepted name: protein N-terminal monomethyltransferase

Reaction: S-adenosyl-L-methionine + N-terminal-(A,P,S)PK-[protein] = S-adenosyl-L-homocysteine + N-terminal-N-methyl-N-(A,P,S)PK-[protein]

Other name(s): NRMT2 (gene name); METTL11B (gene name); N-terminal monomethylase

Systematic name: S-adenosyl-L-methionine:N-terminal-(A,P,S)PK-[protein] monomethyltransferase

Comments: This enzyme methylates the N-terminus of target proteins containing the N-terminal motif [Ala/Pro/Ser]-Pro-Lys after the initiator L-methionine is cleaved. In contrast to EC 2.1.1.244, protein N-terminal methyltransferase, the protein only adds one methyl group to the N-terminal.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:

References:

1. Petkowski, J.J., Bonsignore, L.A., Tooley, J.G., Wilkey, D.W., Merchant, M.L., Macara, I.G. and Schaner Tooley, C.E. NRMT2 is an N-terminal monomethylase that primes for its homologue NRMT1. Biochem. J. 456 (2013) 453-462. [PMID: 24090352]

[EC 2.1.1.299 created 2014]

EC 2.1.1.300

Accepted name: pavine N-methyltransferase

Reaction: S-adenosyl-L-methionine + (±)-pavine = S-adenosyl-L-homocysteine + N-methylpavine

Other name(s): PavNMT

Systematic name: S-adenosyl-L-methionine:(±)-pavine N-methyltransferase

Comments: The enzyme, isolated from the plant Thalictrum flavum, also methylates (R,S)-stylopine and (S)-scoulerine (11%) with lower activity (14% and 11%, respectively).

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:

References:

1. Jain, A., Ziegler, J., Liscombe, D.K., Facchini, P.J., Tucker, P.A. and Panjikar, S. Purification, crystallization and X-ray diffraction analysis of pavine N-methyltransferase from Thalictrum flavum. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 64 (2008) 1066-1069. [PMID: 18997344]

2. Liscombe, D.K., Ziegler, J., Schmidt, J., Ammer, C. and Facchini, P.J. Targeted metabolite and transcript profiling for elucidating enzyme function: isolation of novel N-methyltransferases from three benzylisoquinoline alkaloid-producing species. Plant J. 60 (2009) 729-743. [PMID: 19624470]

[EC 2.1.1.300 created 2014]


Continued with EC 2.1.1.301 to EC 2.1.1.396
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