16S rRNA pseudouridine<sup>516</sup> synthase (, 16S RNA pseudouridine<sup>516</sup> synthase, 16S PsiI<sup>516</sup> synthase, 16S RNA Psi<sup>516</sup> synthase, RNA pseudouridine synthase RsuA, RsuA, 16S RNA pseudouridine 516 synthase) is an enzyme with systematic name 16S rRNA-uridine<sup>516</sup> uracil mutase. This enzyme catalyses the following chemical reaction
The enzyme is specific for uridine<sup>516</sup> in 16S rRNA.