tRNA pseudouridine<sup>55</sup> synthase (, TruB, aCbf5, Pus4, YNL292w (gene), Psi55 tRNA pseudouridine synthase, tRNA:Psi<sup>55</sup>-synthase, tRNA pseudouridine 55 synthase, tRNA:pseudouridine-55 synthase, Psi<sup>55</sup> synthase, tRNA Psi<sup>55</sup> synthase, tRNA:Psi<sup>55</sup> synthase, tRNA-uridine<sup>55</sup> uracil mutase, Pus10, tRNA-uridine<sup>54/55</sup> uracil mutase) is an enzyme with systematic name tRNA-uridine<sup>55</sup> uracil mutase. This enzyme catalyses the following chemical reaction
Pseudouridine synthase TruB from Escherichia coli specifically modifies uridine<sup>55</sup> in tRNA molecules.