IUBMB Enzyme Nomenclature



Accepted name: tRNA pseudouridine38-40 synthase

Reaction: tRNA uridine38-40 = tRNA pseudouridine38-40

For diagram of mechanism click here.

Other name(s): TruA; tRNA pseudouridine synthase I; PSUI; hisT (gene name)

Systematic name: tRNA-uridine38-40 uracil mutase

Comments: The uridylate residues at positions 38, 39 and 40 of nearly all tRNAs are isomerized to pseudouridine. TruA specifically modifies uridines at positions 38, 39, and/or 40 in the anticodon stem loop of tRNAs with highly divergent sequences and structures [1].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 61506-89-6


1. Hur, S. and Stroud, R.M. How U38, 39, and 40 of many tRNAs become the targets for pseudouridylation by TruA. Mol. Cell 26 (2007) 189-203. [PMID: 17466622]

2. Huang, L., Pookanjanatavip, M., Gu, X. and Santi, D.V. A conserved aspartate of tRNA pseudouridine synthase is essential for activity and a probable nucleophilic catalyst. Biochemistry 37 (1998) 344-351. [PMID: 9425056]

3. Kammen, H.O., Marvel, C.C., Hardy, L. and Penhoet, E.E. Purification, structure, and properties of Escherichia coli tRNA pseudouridine synthase I. J. Biol. Chem. 263 (1988) 2255-2263. [PMID: 3276686]

4. Turnbough, C.L., Jr., Neill, R.J., Landsberg, R. and Ames, B.N. Pseudouridylation of tRNAs and its role in regulation in Salmonella typhimurium. J. Biol. Chem. 254 (1979) 5111-5119. [PMID: 376505]

5. Zhao, X. and Horne, D.A. The role of cysteine residues in the rearrangement of uridine to pseudouridine catalyzed by pseudouridine synthase I. J. Biol. Chem. 272 (1997) 1950-1955. [PMID: 8999885]

6. Foster, P.G., Huang, L., Santi, D.V. and Stroud, R.M. The structural basis for tRNA recognition and pseudouridine formation by pseudouridine synthase I. Nat. Struct. Biol. 7 (2000) 23-27. [PMID: 10625422]

7. Dong, X., Bessho, Y., Shibata, R., Nishimoto, M., Shirouzu, M., Kuramitsu, S. and Yokoyama, S. Crystal structure of tRNA pseudouridine synthase TruA from Thermus thermophilus HB8. RNA Biol 3 (2006) 115-122. [PMID: 17114947]

8. Arena, F., Ciliberto, G., Ciampi, S. and Cortese, R. Purification of pseudouridylate synthetase I from Salmonella typhimurium. Nucleic Acids Res. 5 (1978) 4523-4536. [PMID: 370771]

[EC created 1990, modified 2011]

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