Official Full Name
O-Glycosidase
Background
O-Glycosidase releases unsubstituted Ser-and Thr-linked β-Gal-(1→3)-α-GalNAc (Core 1 type O-glycan) from glycoproteins. Substitutions of the disaccharide core with sialic acid, lactosamine (galactose-N-acetyl glucosamine), or fucose will block hydrolysis and prevent the liberation of the oligosaccharide from the protein. Pretreament with glycolytic enzymes to remove substituent saccharides from the O-glycan may be needed prior to cleavage using O-glycosidase.
Synonyms
endo-α-acetylgalactosaminidase; endo-α-N-acetyl-D-galactosaminidase; mucinaminylserine mucinaminidase; D-galactosyl-3-(N-acetyl-α-D-galactosaminyl)-L-serine mucinaminohydrolase; endo-α-GalNAc-ase; glycopeptide α-N-acetylgalactosaminidase; D-galactosyl-N-acetyl-α-D-galactosamine D-galactosyl-N-acetyl-galactosaminohydrolase; 9032-92-2; EC 3.2.1.97
O-glycosidases are a class of enzymes that catalyze the hydrolysis of O-glycosidic bonds between sugar residues and proteins or lipids. These enzymes play a key role in the regulation of various biochemical pathways and have a wide range of applications in biotechnology and medicine. O-glycosylation is a common and post-translational modification process involving the attachment of sugar residues to the hydroxyl groups of serine or threonine amino acids in proteins or lipids. O-glycosylation is a ubiquitous modification that plays a key role in numerous cellular processes, including receptor signaling, protein folding, and cell adhesion.O-glycosidases are enzymes that catalyze the removal of O-glycosylated sugar residues, which often affects the function and stability of glycosylated proteins or lipids.
Structure
O-glycosidases are enzymes belonging to the glycoside hydrolase family (GH), whose structures vary considerably depending on their specific substrate specificity and catalytic mechanism. GH enzymes typically consist of an (α/β)8 barrel-folded core with two or more conserved catalytic residues, including a nucleophile and an acid/base. o-glycosidases may also contain other protein structural domains involved in substrate binding or complex formation or subunits.
Distribution
O-glycosidases are present in almost all organisms and are involved in the regulation of numerous physiological and pathological processes. These enzymes are expressed in a variety of tissues and organs, including the liver, kidney, brain and intestine. In mammals, O-glycosidases are involved in the regulation of protein degradation, lysosomal degradation and sugar recycling. Bacterial and fungal O-glycosidases are involved in the degradation of complex carbohydrates in the environment and play an important role in their respective ecosystems.
Functions
The main function of O-glycosidases is to regulate the turnover and cycling of glycosylated proteins or lipids. o-Glycosidases can cleave the O-glycosidic bond between a sugar residue and a protein or lipid, releasing the sugar residue and allowing degradation or modification of the glycosylated substrate. o-Glycosidases may also play a key role in the processing and maturation of glycoproteins and glycolipids, including regulation of receptor signaling, cell adhesion, and immune recognition.
Applications
O-glycosidases have many applications in biotechnology and medicine, including the production of glycoproteins and glycolipids, the analysis of glycan structures, and the development of therapeutic and diagnostic methods. In the production of glycoproteins and glycolipids, O-glycosidases are often used as deglycosylase supplements for recombinantly produced glycoproteins, resulting in homogeneous protein products with the desired properties. In the analysis of glycan structures, O-glycosidases are used to remove specific O-glycosylated sugar residues, allowing the identification and quantification of specific glycan structures.
Clinical Significance
O-glycosidases have potential clinical relevance in the diagnosis, treatment and prevention of various diseases. Abnormal O-glycosylation is a hallmark of many pathological conditions, including cancer, cardiovascular disease, and neurodegenerative disorders. o-Glycosidases have been used to diagnose lysosomal storage disorders (LSDs), which are characterized by the accumulation of undegraded sugar conjugates in lysosomes. o-Glycosidases may also have potential applications in the treatment of LSDs, as they enhance the degradation of sugar conjugates and reduce their lysosomal accumulation.
Conclusion
O-glycosidases are key enzymes involved in the regulation of O-glycosylation, an important modification that plays a key role in many cellular processes. These enzymes have a wide range of applications in biotechnology and medicine, including the production of glycoproteins and glycolipids, the analysis of glycan structures, and the development of therapeutic and diagnostic approaches.
