Α-Galactosidase

Human α‑galactosidases encoded by GLA and MYORG genes share a conserved modular architecture built around a TIM barrel catalytic domain with additional β‑sandwich accessory domains. The lysosomal enzyme α‑galactosidase A (GLA product) is a secreted glycoprotein that forms a homodimer. Each subunit contains an N‑terminal TIM barrel harboring the active site and a C‑terminal antiparallel β‑sandwich, with multiple N‑linked glycans that stabilize the fold and mediate lysosomal targeting via mannose 6-phosphate receptors. In contrast, MYORG is a type I membrane glycoprotein located in the endoplasmic reticulum that also dimerizes and comprises an N‑terminal β‑sandwich‑like domain, a central TIM barrel catalytic domain, and a proximal β‑sheet domain, but it lacks the distal C‑terminal domain typical of other GH31 family members and instead uses an internal insertion region to form its dimer interface. == Function ==

This enzyme is a homodimeric glycoprotein that hydrolyses the terminal α-galactosyl moieties from glycolipids and glycoproteins. It predominantly hydrolyzes ceramide trihexoside, and it can catalyze the hydrolysis of melibiose into galactose and glucose. == Reaction mechanism ==

An α‑galactosidase preparation derived from the mold Aspergillus niger is used as a dietary supplement to improve digestion of oligosaccharides and reduce gas‑related symptoms in individuals with complex carbohydrate intolerance, particularly after consumption of legumes. This mold-derived α‑galactosidase is the active ingredient in Beano, a dietary supplement for bloating and flatulence. Recombinant α-galactosidase made by baker's yeast is approved in Europe as a feed additive intended to make poultry food more digestible. == See also ==