This family represents just the active peptide part of these proteins. Residues 1-120 are not part of the model as they form the pro-peptide, which before cleavage blocks the active site from the substrate. The catalytic residues of histidine and cysteine are brought close together at the active site by the folding of the active peptide.
Jiyao W et al.(2023). "The conserved domain database in 2023.",