Chymotrypsin sequence analysis. (A) Diagrammatic representation of PpChym3 sequence showing the predicted signal peptide (underlined) and the residues of the catalytic triad (H/D/S) marked with a triangle. (B) Sequence alignment of the three Phlebotomus papatasi chymotrypsin-like sequences. Identical residues are highlighted in black and similar residues highlighted in grey. The predicted signal peptides are underlined and the catalytic residues marked with (*) and the accession numbers are in parentheses.