IUBMB Enzyme Nomenclature


Accepted name: tRNA (guanine37-N1)-methyltransferase

Reaction: S-adenosyl-L-methionine + guanine37 in tRNA = S-adenosyl-L-homocysteine + N1-methylguanine37 in tRNA

For diagram of reaction click here.

Other name(s): TrmD; tRNA (m1G37) methyltransferase; transfer RNA (m1G37) methyltransferase; Trm5p; TRMT5; tRNA-(N1G37) methyltransferase; MJ0883 (gene name)

Systematic name: S-adenosyl-L-methionine:tRNA (guanine37-N1)-methyltransferase

Comments: This enzyme is important for the maintenance of the correct reading frame during translation. Unlike TrmD from Escherichia coli, which recognizes the G36pG37 motif preferentially, the human enzyme (encoded by TRMT5) also methylates inosine at position 37 [4].

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


1. Takeda, H., Toyooka, T., Ikeuchi, Y., Yokobori, S., Okadome, K., Takano, F., Oshima, T., Suzuki, T., Endo, Y. and Hori, H. The substrate specificity of tRNA (m1G37) methyltransferase (TrmD) from Aquifex aeolicus. Genes Cells 11 (2006) 1353-1365. [PMID: 17121543]

2. Lee, C., Kramer, G., Graham, D.E. and Appling, D.R. Yeast mitochondrial initiator tRNA is methylated at guanosine 37 by the Trm5-encoded tRNA (guanine-N1-)-methyltransferase. J. Biol. Chem. 282 (2007) 27744-27753. [PMID: 17652090]

3. O'Dwyer, K., Watts, J.M., Biswas, S., Ambrad, J., Barber, M., Brule, H., Petit, C., Holmes, D.J., Zalacain, M. and Holmes, W.M. Characterization of Streptococcus pneumoniae TrmD, a tRNA methyltransferase essential for growth. J. Bacteriol. 186 (2004) 2346-2354. [PMID: 15060037]

4. Brule, H., Elliott, M., Redlak, M., Zehner, Z.E. and Holmes, W.M. Isolation and characterization of the human tRNA-(N1G37) methyltransferase (TRM5) and comparison to the Escherichia coli TrmD protein. Biochemistry 43 (2004) 9243-9255. [PMID: 15248782]

5. Goto-Ito, S., Ito, T., Ishii, R., Muto, Y., Bessho, Y. and Yokoyama, S. Crystal structure of archaeal tRNA(m(1)G37)methyltransferase aTrm5. Proteins 72 (2008) 1274-1289. [PMID: 18384044]

6. Ahn, H.J., Kim, H.W., Yoon, H.J., Lee, B.I., Suh, S.W. and Yang, J.K. Crystal structure of tRNA(m1G37)methyltransferase: insights into tRNA recognition. EMBO J. 22 (2003) 2593-2603. [PMID: 12773376]

[EC created 2011 (EC created 1971, part transferred 2011 to EC]

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