Amino acid sequences of identified CPs were aligned using ClustalW. Greater sequence similarity is indicated by darker background, while locations of signal peptide cleavage, as predicted by SignalP, and of propeptide cleavage, based on experimental evidence for other orthologs, are indicated by a ∧ and #, respectively. Critical active site residues are numbered above the alignment according to their corresponding site in bovine CPA1. Sequences were obtained from the NCBI or Ensembl databases and correspond to the following accession numbers: zCPB1, ENSDARP00000066831; zCPB2, BC095834; zCPO, NM001145629; zCPA1, ENSDARP00000024981; zCPA2, ENSDARP00000064203; zCPA4, ENSDARP00000014821; zCPA5, ENSDARP00000034171; zCPA6, XM001342113.