FIGURE 1.

Alignment of the amino acid sequences of the Escherichia coli TruA and S. cerevisiae Pus1p, Pus2p, and Pus3p tRNA:Ψ-synthases of the TruA family. (A) Proteins are schematically represented as bars, whose lengths are proportional to lengths of the polypeptide chains. Motifs I, II, IIa, III, and IIIa of RNA:Ψ-synthases (Del Campo et al. 2004) are represented by black or gray rectangles. (B) The alignments of the amino acid sequences of the conserved blocks I to IIIa are shown. Identical and semiconserved residues are boxed. The thickness of the line is an indication of the level of sequence conservation. The conserved residues (D, Y, I, R, L) in the tRNA:Ψ-synthases active sites are indicated by asterisks.