IUBMB Enzyme Nomenclature


Accepted name: tRNAPhe {7-[3-amino-3-(methoxycarbonyl)propyl]wyosine37-N}-methoxycarbonyltransferase

Reaction: S-adenosyl-L-methionine + 7-[(3S)-3-amino-3-(methoxycarbonyl)propyl]wyosine37 in tRNAPhe + CO2 = S-adenosyl-L-homocysteine + wybutosine37 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-(methoxycarbonyl)propyl]wyosine37-N}-methyltransferase (carbon dioxide-adding)

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-(methoxycarbonyl)propyl]wyosine37 in tRNAPhe as substrate. The enzyme also has the activity of EC, tRNAPhe [7-(3-amino-3-carboxypropyl)wyosine37-O]-methyltransferase [2].

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


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 created 2013]

Return to EC 2.3.1 home page
Return to EC 2.3 home page
Return to EC 2 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page