Catabolism of glycans

Based on its primary sequence, mannosidase II is a member of the class II mannosidase family (CAZy glycohydrolase family 38, which includes also the lysosomal mannosidase involved in glycoprotein catabolism). Like the lysosomal enzyme, mannosidase II is inhibited by swain-sonine [62], thus this reagent can be used to block the formation of complex A-glycans. The... 

Fig. 17.4 Simplified structure of a complex N-linked glycan and the sites of action of B-hexosaminidase. Glycoproteins are degraded by specific enzymes from both directions. Lysosomal catabolism is terminated when an A-acetylglucosamine residue is encountered by the catalytically impaired enzyme B-hexosaminidase, and thus the glycoprotein-derived oligosaccharide in the box accumulates in Sandhoff patients.

Roles of N- and 6 -Linked Glycans and Compaitmentalization of Biosynthetic and Catabolic Reactions... 

Strecker, G. Michalski, J.C. Montreuil, J. Lysosomal Catabolic Pathway of N-Glycosylprotein Glycans. Biochemie, 1988, 70, 1505-1510. 

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