Glycoside hydrolase family 29

In molecular biology, glycoside hydrolase family 29 is a family of glycoside hydrolases.

Glycoside hydrolases 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 glycoside hydrolases, based on sequence similarity, has led to the definition of 100 different families. This classification is available on the CAZy web site, and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes.

Glycoside hydrolase family 29 includes alpha-L-fucosidases, They are lysosomal enzymes responsible for hydrolyzing the alpha-1,6-linked fucose joined to the reducing-end N-acetylglucosamine of the carbohydrate moieties of glycoproteins. Alpha-L-fucosidase is responsible for hydrolysing the alpha-1,6-linked fucose joined to the reducing-end N-acetylglucosamine of the carbohydrate moieties of glycoproteins.

Fucosylated glycoconjugates are involved in numerous biological events, making alpha-l-fucosidases, the enzymes responsible for their processing, critically important. Deficiency in alpha-l-fucosidase activity is associated with fucosidosis, a lysosomal storage disorder characterised by rapid neurodegeneration, resulting in severe mental and motor deterioration. The enzyme is a hexamer and displays a two-domain fold, composed of a catalytic (beta/alpha)(8)-like domain and a C-terminal beta-sandwich domain.

Drosophila melanogaster spermatozoa contains an alpha-l-fucosidase that might be involved in fertilisation by interacting with alpha-l-fucose residues on the micropyle of the eggshell. In human sperm, membrane-associated alpha-l-fucosidase is stable for extended periods of time, which is made possible by membrane domains and compartmentalisation. These help preserve protein integrity.