IUBMB Enzyme Nomenclature


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:


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 created 2013, modified 2014]

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