FIG. 1.

Sequence comparison of the PP (CP and aminoacylase activities) from P. horikoshii, the CP from S. solfataricus, and the aminoacylase from B. stearothermophilus (top, middle, and bottom, respectively). Dashes indicate gaps. Numbers on the left represent the position of the first residue in the original sequence. Conserved residues between PP and CPS and among the three enzymes are marked with pluses and asterisks, respectively. The seven major homology blocks (B1 through B7) in CPs were assigned by Colombo et al. (13), and the putative residues participating in the activity are in bold.