IUBMB Enzyme Nomenclature


Accepted name: tRNAPhe (4-demethylwyosine37-C7) aminocarboxypropyltransferase

Reaction: S-adenosyl-L-methionine + 4-demethylwyosine37 in tRNAPhe = S-methyl-5′-thioadenosine + 7-[(3S)-3-amino-3-carboxypropyl]-4-demethylwyosine37 in tRNAPhe

For diagram of reaction, click here

Glossary: 4-demethylwyosine = imG-14 = 6-methyl-3-(β-D-ribofuranosyl)-3,5-dihydro-9H-imidazo[1,2-a]purin-9-one
7-[(3S)-3-amino-3-carboxypropyl]-4-demethylwyosine = yW-89

Other name(s): TYW2; tRNA-yW synthesizing enzyme-2; TRM12 (gene name); taw2 (gene name)

Systematic name: S-adenosyl-L-methionine:tRNAPhe (4-demethylwyosine37-C7)-[(3S)-3-amino-3-carboxypropyl]transferase

Comments: The enzyme, which is found in all eukaryotes and in the majority of Euryarchaeota (but not in the Crenarchaeota), is involved in the hypermodification of the guanine nucleoside at position 37 of tRNA leading to formation of assorted wye bases. This modification is essential for translational reading-frame maintenance. The eukaryotic enzyme is involved in biosynthesis of the tricyclic base wybutosine, which is found only in tRNAPhe.

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


1. Umitsu, M., Nishimasu, H., Noma, A., Suzuki, T., Ishitani, R. and Nureki, O. Structural basis of AdoMet-dependent aminocarboxypropyl transfer reaction catalyzed by tRNA-wybutosine synthesizing enzyme, TYW2. Proc. Natl. Acad. Sci. USA 106 (2009) 15616-15621. [PMID: 19717466]

2. Rodriguez, V., Vasudevan, S., Noma, A., Carlson, B.A., Green, J.E., Suzuki, T. and Chandrasekharappa, S.C. Structure-function analysis of human TYW2 enzyme required for the biosynthesis of a highly modified Wybutosine (yW) base in phenylalanine-tRNA. PLoS One 7 (2012) e39297. [PMID: 22761755]

3. de Crecy-Lagard, V., Brochier-Armanet, C., Urbonavicius, J., Fernandez, B., Phillips, G., Lyons, B., Noma, A., Alvarez, S., Droogmans, L., Armengaud, J. and Grosjean, H. Biosynthesis of wyosine derivatives in tRNA: an ancient and highly diverse pathway in Archaea. Mol Biol Evol 27 (2010) 2062-2077. [PMID: 20382657]

[EC created 2013]

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