InterPro: IPR000602 Glycoside hydrolase, family 38, core

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.

Glycoside hydrolase family 38 GH38 comprises enzymes with only one known activity; alpha-mannosidase (EC:3.2.1.24) (EC:3.2.1.114).

Lysosomal alpha-mannosidase is necessary for the catabolism of N-linked carbohydrates released during glycoprotein turnover. The enzyme catalyses the hydrolysis of terminal, non-reducing alpha-D-mannose residues in alpha-D-mannosides, and can cleave all known types of alpha-mannosidic linkages. Defects in the gene cause lysosomal alpha-mannosidosis (AM), a lysosomal storage disease characterised by the accumulation of unbranched oligo-saccharide chains.