Multiple sequence alignment. Wild type guinea pig preprochymase (GPα) amino acid sequence is compared with that of orthologous mouse and human α-chymases (Humα and Musα, respectively). Putative signal and propeptide segments are italicized and underlined, respectively. Chymase-specific numbering begins with Met-21, which is the first residue of the signal peptide. The mature catalytic domain begins at Val1. Key residues in the catalytic domain are also numbered in italics using standard chymotrypsinogen numbering. ▾, sites of hydrolysis by signal peptidase and dipeptidylpeptidase I or of autolysis; • and #, catalytic and specificity triad residues, respectively; †, predicted sites of N-glycosylation. The human and mouse chymase sequences are from GenBank™ files M64269 and NP_034910, respectively.