Glycogen-debranching enzyme

This is due to the absence of the debranching enzyme. Glycogen accumulates because only the outer portion of the branches can be removed by phosphorylase. Thus, a highly branched glycogen accumulates and, because glycogen degradation is incomplete, there is an occasional mild hypoglycemia. 

FIGURE 23.15 The reactions of glycogen debranching enzyme. Transfer of a group of three o -(l 4)-linked glucose residues from a limit branch to another branch is followed by cleavage of the o -(l 6) bond of the residue... 

The glycogen phosphorylase reaction degrades glycogen to produce limit dextrins, which are further degraded by debranching enzyme, as already described. 

Tabata, S. and Dohi, Y., An assay for oligo-(l—>4) —5(1—>4)-glucantransferase activity in the glycogen debranching enzyme system by using HPLC with a pulsed amperometric detector, Carb. Res., 230,179, 1992. 

Debranching enzyme deconstructs the branches in glycogen that have been exposed by glycogen phosphorylase. The two-step process by which this occurs is diagrammed in Figure 1-14-4. Debranching enzyme ... 

III Cori Glycogen debranching enzyme Mild hypoglycemia, liver enlargement Short outer branches Single glucose residue at outer branch... 

GLYCINE REDUCTASE GLYCINE SYNTHASE Glycogen debranching enzyme, DEBRANCHING ENZYME Glycogenolysis tracer kinetics,... 

Figure 6-5. Glycogenolysis. Degradation of glycogen occurs stepwise by hydrolysis of one glucosyl unit at a time from the nonreducing ends by phosphorylase. The limit dextrin occurs as indicated in the second step when there are four glucosyl units remaining to a branch point. Once debranching enzyme has resolved the limit dextrin, degradation by phosphorylase can resume.

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... 

Glycogen degradation requires two enzymes glycogen phosphorylase and glycogen-debranching enzyme. 

The Coordinated Action of the Two Glycogen Debranching Enzyme Activities on Phosphorylase Limit Dextrin... 

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