To generate the bioactive form of insulin (and many other peptides), a second step involving the removal of C-terminal basic residues is required; this step is mediated by carboxypeptidases E and/or D. PC2 plays only a minor role in the first step of insulin biosynthesis, but a greater role in the first step of glucagon biosynthesis compared to PC1.

7B2 accomplishes this by preventing the aggregation of proPC2 to inactivatable forms.

The C-terminal domain of 7B2 also inhibits PC2 activity until it is cleaved into smaller inactive forms that lack carboxy-terminal basic residues.

[5] In humans, proprotein convertase 2 is encoded by the PCSK2 gene.

[6] It is related to the bacterial enzyme subtilisin, and altogether there are 9 different subtilisin-like genes in mammals: furin, PACE4, PC4, PC5/6, PC7/8, PCSK9, and SKI1/S1P.