This family features sequences that are similar to a region of the Flavobacterium heparinum proteins heparinase II (Swiss:Q46080) and heparinase III (Swiss:Q59289). 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 [1].

1: Isolation and expression in Escherichia coli of hepB and hepC, genes coding for the glycosaminoglycan-degrading enzymes heparinase II and heparinase III, respectively, from Flavobacterium heparinum. Su H, Blain F, Musil RA, Zimmermann JJ, Gu K, Bennett DC; Appl Environ Microbiol 1996;62:2723-2734. PMID:8702264

2: Structural basis of heparan sulfate-specific degradation by heparinase III. Dong W, Lu W, McKeehan WL, Luo Y, Ye S; Protein Cell. 2012;3:950-961. PMID:23011846