Glycogen storage disease type III

Chen YT, He JK, Ding JH, Brown BI (1987) Glycogen debranching enzyme purification, antibody characterization, and immunoblot analysis of type III glycogen storage disease. Am J Hum Genet 41 1002-1015... 

Other investigators have also differentiated the two activities. The apparent absence of transferase but not glucosidase activity has been proposed as a subclass of type III glycogen storage disease (37). Exposure of the enzyme to guanidine inhibited glucosidase activity on "fast B5" to a greater extent than the combined activity on "63-a-maltotriosylmaltotetraose"... 

In the relative absence of amylo-1,6-glucosidase, as in Type III glycogen-storage disease, glycogen breakdown is incomplete and is limited to the exterior chains. The enzyme therefore fulfils an important in vivo role. 

In limit dextrinosis (type III glycogen storage disease), the glycogen that accumulates has an ahnormal stmcture. Based on the information given in the table, explain what this stnicture might he and why it comes about. 

Several types of glycogen-storage disease are now known in most cases, the accumulation of glycogen can be correlated with a relative deficiency of either n-glucose 6-phosphatase or the debranching-enzyme system (Type I and III disease, respectively). In a very few cases, the enzymic defect is either in branching enzyme or in phosphorylase (Type IV or VI disease, respectively) see Table VII. In the Type II and V diseases, the enzyme deficiencies are different from the above, but have not yet been fully identified. 

Galvin-Parton P, Hommes FA (1996) Abnormal oligosaccharide pattern in glycogen storage disease type III. J Inherit Metab Dis 19 383-384... 

Labrnne, R, Trioche, P., Duvaltier, L, Chevalier, R, Odievre, M. Hepatocellular adenomas in glycogen storage disease type I and III a series of 43 patients and review of the literature. J. Pediatr. Gastroenterol. Nutr. 1997 24 276 - 279... 

Glycogen Storage Disease Type III Debranching Enzyme Deficiency. 304... 

Glycogen storage disease type III Debranching enzyme AGL ... 

Dosman, J., Crawhall, J.C., Klassen, G.A., Mamer, O.A. and Neumann, P. (1974), Urinary excretion of Ce-C lo dicarboxylic acids in glycogen storage diseases types I and III. Clin. Chim. Acta, 51,93. 

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