Protein-glucosylgalactosylhydroxylysine glucosidase (PGGHG)

Protein-glucosylgalactosylhydroxylysine glucosidase (PGGHG) is an enzyme encoded by the ATHL1 gene that belongs to the glycoside hydrolase family 65 (GH65)[1][3][5]. It specifically cleaves glucose from the disaccharide α-d-glucopyranosyl-(1→2)-β-d-galactopyranose units attached to hydroxylysine residues of collagen and collagen-like proteins[1][3]. This activity is a key step in collagen modification and metabolism, with important roles in the structure and function of the extracellular matrix[2][3][5]. PGGHG is implicated in diseases such as osteogenesis imperfecta type V and osteoporosis due to its involvement in collagen processing[5]. The enzyme is predicted to localize mostly in the cytosol and is essential for proper carbohydrate metabolic processes, particularly those influencing collagen secretion, fibril alignment, and tissue homeostasis[5][6]. Site-directed mutagenesis has identified several critical carboxyl residues (Asp301, Glu430, and Glu574) as part of its catalytic site[1][3].

Other names

ATHL1Acid trehalase-like protein 1Testicular tissue protein Li 25Acid trehalase-like 1PGGHG_HUMANProtein-glucosylgalactosylhydroxylysine glucosidase (EC 3.2.1.107)