A family including aminopeptidase P, aminopeptidase M, and prolidase. Also known as metallopeptidase family M24. This family of enzymes is able to cleave amido-, imido- and amidino-containing bonds. Members exibit relatively narrow substrate specificity compared to other metallo-aminopeptidases, suggesting they play roles in regulation of biological processes rather than general protein degradation.

Heparinase II/III-like protein. This family features sequences that are similar to a region of the Flavobacterium heparinum proteins heparinase II and heparinase III. The former is known to degrade heparin and heparin sulphate, whereas the latter predominantly degrades heparin sulphate. Both are secreted into the periplasmic space upon induction with heparin.