This family consists of (Uracil-5-)-methyltransferases EC:2.1.1.35 from bacteria, archaea and eukaryotes. A 5-methyluridine (m(5)U) residue at position 54 is a conserved feature of bacterial and eukaryotic tRNAs. The methylation of U54 is catalysed by the tRNA(m5U54)methyltransferase, which in Saccharomyces cerevisiae is encoded by the nonessential TRM2 gene. It is thought that tRNA modification enzymes might have a role in tRNA maturation not necessarily linked to their known catalytic activity [1].

1: Dual function of the tRNA(m(5)U54)methyltransferase in tRNA maturation. Johansson MJ, Bystrom AS; RNA 2002;8:324-335. PMID:12003492