Glycoside hydrolase, family 13, N-terminal Ig-like domain (IPR004185)

Short name: Glyco_hydro_13_lg-like_dom

Overlapping homologous superfamilies

Domain relationships



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 [PMID: 7624375, PMID: 8535779]. This classification is available on the CAZy (CArbohydrate-Active EnZymes) web site.

E or "early" set domains are associated with the catalytic domain of the cyclomaltodextrinase (CDase) and pullulan-degrading enzymes at the N-terminal end. The N-terminal domain of the CDase and pullulan-degrading enzymes may be related to the immunoglobulin and/or fibronectin type III superfamilies. This domain may be involved in homodimeric/tetrameric/dodecameric interactions. Enzymes containing this domain belong to family 13 (GH13) of the glycosyl hydrolases. Members of this subgroup include CDase, maltogenic amylase, and neopullulanase, all of which are capable of hydrolyzing all or two of the following three types of substrates: cyclomaltodextrins (CDs), pullulan, and starch. These enzymes hydrolyze CDs and starch to maltose and pullulan to panose by cleavage of alpha-1,4 glycosidic bonds whereas alpha-amylases essentially lack activity on CDs and pullulan. They also catalyze transglycosylation of oligosaccharides to the C3-, C4- or C6-hydroxyl groups of various acceptor sugar molecules [PMID: 11923309, PMID: 10825529, PMID: 12530525, PMID: 15239382].

GO terms

Biological Process

GO:0005975 carbohydrate metabolic process

Molecular Function

GO:0004553 hydrolase activity, hydrolyzing O-glycosyl compounds

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.