IUBMB Enzyme Nomenclature


Accepted name: tRNA pseudouridine38/39 synthase

Reaction: tRNA uridine38/39 = tRNA pseudouridine38/39

For diagram of mechanism click here.

Other name(s): Deg1; Pus3p; pseudouridine synthase 3

Systematic name: tRNA-uridine38/39 uracil mutase

Comments: The enzyme from Saccharomyces cerevisiae is active only towards uridine38 and uridine39, and shows no activity with uridine40 (cf. EC, tRNA pseudouridine38-40 synthase) [1]. In vitro the enzyme from mouse is active on uridine39 and very slightly on uridine38 (human tRNALeu) [2].

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


1. Lecointe, F., Simos, G., Sauer, A., Hurt, E.C., Motorin, Y. and Grosjean, H. Characterization of yeast protein Deg1 as pseudouridine synthase (Pus3) catalyzing the formation of Ψ38 and Ψ39 in tRNA anticodon loop. J. Biol. Chem. 273 (1998) 1316-1323. [PMID: 9430663]

2. Chen, J. and Patton, J.R. Pseudouridine synthase 3 from mouse modifies the anticodon loop of tRNA. Biochemistry 39 (2000) 12723-12730. [PMID: 11027153]

[EC created 2011]

Return to EC 5.4.99 home page
Return to EC 5.4 home page
Return to EC 5 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page