A flavoprotein (FAD). Up to 25% of the bases in mature tRNA are post-translationally modified or hypermodified. One almost universal post-translational modification is the conversion of U54 into ribothymidine in the T¦·C loop, and this modification is found in most species studied to date [2]. Unlike this enzyme, which uses 5,10-methylenetetrahydrofolate and NAD(P)H to supply the atoms for methylation of U54, EC 2.1.1.35, tRNA (uracil54-C5)-methyltransferase, uses S-adenosyl-L-methionine.
Cofactor
History
Reactions
5,10-methylenetetrahydrofolate + uracil(54) in tRNA + FADH(2) = tetrahydrofolate + 5-methyluracil(54) in tRNA + Fad.