InterPro: IPR005199 Glycoside hydrolase family 79, N-terminal

O-Glycosyl hydrolases EC:3.2.1. are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycosyl hydrolases, based on sequence similarity, has led to the definition of 85 different families [1, 2, 3]. This classification is available on the CAZy (CArbohydrate-Active EnZymes) web site [4]. Because the fold of proteins is better conserved than their sequences, some of the families can be grouped in clans.

This is a family of endo-beta-N-glucuronidase, or heparanase belonging to glycoside hydrolase family 79 (GH79). Heparan sulphate proteoglycans (HSPGs) play a key role in the self- assembly, insolubility and barrier properties of basement membranes and extracellular matrices. Hence, cleavage of heparan sulphate (HS) affects the integrity and functional state of tissues and thereby fundamental normal and pathological phenomena involving cell migration and response to changes in the extracellular microenvironment. Heparanase degrades HS at specific intrachain sites. The enzyme is synthesized as a latent approximately 65 kDa protein that is processed at the N terminus into a highly active approximately 50 kDa form. Experimental evidence suggests that heparanase may facilitate both tumor cell invasion and neovascularization, both critical steps in cancer progression. The enzyme is also involved in cell migration associated with inflammation and autoimmunity [5].