Endotransglucosylases

Endotransglucosylases are a class of enzymes that catalyze the transfer of glucosyl groups within a polysaccharide chain, resulting in the formation of a new glycosidic bond. These enzymes play a crucial role in the biosynthesis and modification of polysaccharides, which are essential components of the cell wall, extracellular matrix, and storage granules in various organisms. Endotransglucosylases are found in a wide range of organisms, including plants, fungi, bacteria, and archaea, and their specificities and mechanisms vary depending on the organism and the polysaccharide substrate.

The catalytic mechanism of endotransglucosylases typically involves the formation of a glucosyl-enzyme intermediate, which is then transferred to an acceptor site within the polysaccharide chain. The specificity of these enzymes is determined by the structure of the polysaccharide substrate and the spatial arrangement of the active site residues. Endotransglucosylases can be classified into different families based on their sequence homology and catalytic mechanism, such as the glycoside hydrolase family 13 (GH13) and the glycoside hydrolase family 16 (GH16).

Endotransglucosylases have been extensively studied due to their potential applications in biotechnology, such as the production of biofuels, the modification of polysaccharide-based materials, and the development of therapeutic agents. For example, endotransglucosylases have been used to degrade cellulose for the production of biofuels, and to modify starch for the development of functional foods and pharmaceuticals. Additionally, endotransglucosylases have been implicated in various diseases, such as cancer and inflammatory disorders, and their inhibition or activation has been proposed as a potential therapeutic strategy.