IUBMB Enzyme Nomenclature


Accepted name: tRNA (guanine26-N2)-dimethyltransferase

Reaction: 2 S-adenosyl-L-methionine + guanine26 in tRNA = 2 S-adenosyl-L-homocysteine + N2-dimethylguanine26 in tRNA

Other name(s): Trm1p; TRM1; tRNA (m22G26)dimethyltransferase

Systematic name: S-adenosyl-L-methionine:tRNA (guanine26-N2)-dimethyltransferase

Comments: The enzyme dissociates from its tRNA substrate between the two consecutive methylation reactions. In contrast to EC, tRNA (guanine26-N2/guanine27-N2)-dimethyltransferase, this enzyme does not catalyse the methylation of guanine27 in tRNA.

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


1. Constantinesco, F., Motorin, Y. and Grosjean, H. Characterisation and enzymatic properties of tRNA(guanine26, N2,N2-dimethyltransferase (Trm1p) from Pyrococcus furiosus. J. Mol. Biol. 291 (1999) 375-392. [PMID: 10438627]

2. Constantinesco, F., Benachenhou, N., Motorin, Y. and Grosjean, H. The tRNA(guanine-26,N2-N2) methyltransferase (Trm1) from the hyperthermophilic archaeon Pyrococcus furiosus: cloning, sequencing of the gene and its expression in Escherichia coli. Nucleic Acids Res. 26 (1998) 3753-3761. [PMID: 9685492]

3. Liu, J., Liu, J. and Straby, K.B. Point and deletion mutations eliminate one or both methyl group transfers catalysed by the yeast TRM1 encoded tRNA (m22G26)dimethyltransferase. Nucleic Acids Res. 26 (1998) 5102-5108. [PMID: 9801306]

4. Liu, J., Zhou, G.Q. and Straby, K.B. Caenorhabditis elegans ZC376.5 encodes a tRNA (m22G26)dimethyltransferance in which 246arginine is important for the enzyme activity. Gene 226 (1999) 73-81. [PMID: 10048958]

[EC created 2011 (EC created 1972, part transferred 2011 to EC]

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